How should I phrase this? I need to message my chem teacher about asking to re-test, but I don't know how to say it. I'm thinking maybe just "can I re-test next week?" or "can I possibly re-test next week?" but I don't know if that's too short. I'm trying to be as polite as possible.

You could say "Is it possible that I can re-take the test next week?" and follow that with reasons because he or she probably wouldn't just let you re-test. Maybe say that you were busy and didn't have time to study or you weren't feeling well when you took the test.

i will try let me see what they are first