Right now I am taking doxy-cycl hycl 100mg cap mutal, am I still allowed to smoke weed?

No. Mj is illegal and dangerous. Using it is never acceptable whether or not you're using Amoxicillin or doxycycline. Excellent studies have shown that mj use prior to adulthood results in dropped iq points (8-10 points in the study from new zealand). Additionally there are hundreds of studies indicating dangers of mj use in many body systems. Best to avoid completely.
Smoking weed. No . Smoking weed is not a good option , it can cause u to be in a motivational state ( and at u age u need to be motivated to accomplish something , in addition weed can cause u symptoms similar to schizophrenia ).