I agree with the advice of the above posters.

I'd also like to offer that choosing classes can induce high anxiety in many, many students. So I hope that fact that you're feeling anxious over classes isn't making you even more anxious, like a snowball effect.

Also, have you seen if you can take courses through other departments that may count towards your degree credits? I remember feeling relieved, finding that a Kinesiology course and some particular Anthropology courses could be taken for credit towards my Psych degree.

Finally, if your college department has a talented undergraduate/graduate (whichever you may be) coordinator or class counsellor, they may be worth talking to. They may be able to offer valuable insight.