No. it should not be the same as a 7 iron... Sand wedges are suppose to be smooth and easy 3/4 swings. Also hit 100 balls on the range doing this to regain your confidence. This will help you shed strokes and be confident and more aggressive. make sure your stance is not too wide as well.

Assuming you are right-handed, hitting some wedge shots on the range with your right foot dropped back about 18 inches should help correct ur swing plane which is usually the cause of the shanks.  Once you do this for a few swings to build confidence, try some easy swings with your wedges.  Hopefully, this will find you with more confidence on those shots and sticking them close more often.

With wedges I find myself never taking a swing longer than 3/4's, it could you're over extending and pulling the club in a different direction. Try taking what you feel is a 3/4 swing with that sand wedge and see if that helps.

I used to have the same problem with a lob wedge.  Keep in mind that what worked for me may not work for you.

A sand wedge is also 1/2" shorter than a 9 or PW (given that Titleist standard length for a SW is 35.25", the PW is 35.75" and the 9 iron is 36")

My 9 iron and PW are 35.5" and I have the lie angle set to 64.5*.  My SW and LW are set to 65*.   The golf swing between a 9 iron and a lob wedge should be just about the same - ball in the center of the stance.   The 8 iron is slightly ahead of center..

Most people never think about making the sand wedge or lob wedge 1/2* more upright vs the 9 iron and PW.  Too flat of a lie angle causes numerous swing faults (one is the toe makes contact with the ground and causes a push shot).

What causes a shank is a loss of balance that causes you to fall for  ward and hit the ball with the hosel. 

Also consider a more compact backswing, 

Another thing that causes a shank is standing too close to the ball.  Stand a little further from the ball and flex the knees a little bit.

What also might help with your sand wedge is to practice choke down shots with a PW.   Along this line may want to consider swinging easier with the SW.  The pont here is to hit a choke shot you need a more controlled swing.

I would consider several things:

1) Take a look at the bounce on your wedge - it might be too much for a fairway shot.  It might be perfect for a "digger" style shot (which would come in handy in the bunkers), but it might be a poor choice from a fairway or hard pan lie.

2) Shorten your swing - lower the number of places where your swing can "get out of sync".

3) Contact your local PGA for a lesson.  This certainly will assist in determining if the problem is swing related, or club related.

It is going to sound cliche, but if you are freaking out before hitting much of your problem could be mental.  I try to follow the same regimen before every single shot, take a deep breath, clear your mind and just focus on the ball, try to find something that helps you relax, and just let your swing do what it does

Definitely work on your setup, swing, and tempo for the shot. Keep your head on the ball through impact and pretend there is a dime sitting under the ball you want to see after it moves. You may also consider buying cavity back wedges that might sooth your mind instead of having a blade wedge. I know png makes a great cavity back wedge that is easy to hit.

I had the same problem for about a two week span last summer. But I then realized that I was standing too close to the ball, which resulted me in hitting every shot off the heel. I stepped a little further from the ball, and had my arms a little bit more extended. I made a conscience effort to hit the ball near the toe, and bam..Back to normal.

Also, open your stance a little bit when using wedges so you can get good hip movement. You want to use a lot of your hips to make a clean wedge shot that checks up.

Standing too close to the ball DOES tend to promote blocks and shanks.  Arms should be slightly extended at address and ball in relation to torso should be where it lines up with your shirt pocket (should be apparently in the center of your stance because it is narrower). 

Maintain a stable base.  Flex the knees a little bit more (also a must when choking down).

More compact backswing.

Not trying to knock the snot out of your wedges.  I know that my full shot is 110 yards and my full open stance pitch is 80 yards with a conservative swing.  I can choke down for 90 or 100 yards on my full square stance swing.

Pitch whenever possible. I would say that probably 90 percent of my wedge shots are played with an open stance.  If I REALLY get lazy or want to hit a 100 yard shot in high winds, I'll pitch an 8 iron.

Bounce isn't an issue.  I play SM4 52-12 and 60-10 (both bent 1* strong).  You take out the bounce by moving your feet more forward (causes the shaft to lean more forward); ball is in the same spot relative to your torso but appears "back" in the stance.  I've played a 54-14 off a tight lie with no issues.

Lastly, read some of Dave Pelz' tips about distance control.