Hi BlueSky
About that ripcord thing, sounds like it could be that the closing loop on the gear you've been jumping is too small... Do you pack the rig yourself? It might just be that the parachute has not been packed tightly enough to fit in the bag properly...?
Before you head up there again, you should just check the rip cord by pulling it out a fraction... Make sure that it is will come out smoothly (just make sure that you push it all the way back in again before you get in the plane!).
Sometimes it is just a matter of putting a bit of sillicone on the rip cord to 'grease' it up a little bit. Another thing to check is that the cord doesn't have any splinters or isn't cracked anywhere cause that could make it get caught too.
Whatever the problem, ask one of the instructors on your DZ - they should be able to fix it for ya!
Don't worry, I'm sure your muscles are fine! Its nice to be important, but more important to be nice.