Okay, so upon not being able to sleep tonight for worry, I've decided on a semi-decent plan of action. Hopefully, this will work.
1.) Use tomorrow to go through the tests I've taken in all my classes thus far, and find out where exactly I'm not grasping the key concepts, paying special attention to physics, as that's the class I know I need the most help in. (Also, call work and tell them I can't work Thursday for the hours they have me scheduled (or at all on Thursdays, really), and to actually look at the availability schedule I posted.)
2.) Ask someone, be it the professor, the student help center, or even my roommates, to see if they can clarify.
3.) Go to all my classes Thursday and Friday, take notes, and do the homework, the way I'm supposed to be doing.
4.) This weekend, retake the tests, to see if I have understood the material.
5.) If the result of 4 is "no", seek out more help, possibly from another source.