Yeah, over-reacting like that is a big problem in soccer, but some of the time those guys are legitimately hurt, imagine running full speed and then having some guy slide into you an directly hit your ankle with his cleat. It sucks and is really painful, so some of the time its acting, some of the time they are just making sure they are ok. You usually can tell because the fakers roll around excessively and look like they've been shot, but the ones that are hurt just lay there in pain.
Anyways, to the menke, I would also recommend that you get a soccer ball involved with you're speed training. Try putting a couple of cones or something in random places in you're yard, then dribble over to one, as soon as you reach it do a little move, like a stepover, change directions, and dribble as fast as you can to another cone. When you reach the other cone, slow down and dribble half speed to another cone and repeat. I like doing that because it works on quick bursts of speed, and I can improve my touch. Plus you are always moving rather than running for 2 miles at a constant speed. I also run about 2-3 miles, 5 times a week for soccer.