Were you having frequent urination while taking propecia? Since propecia is used to treat Benign Prostatic Hypertrophy in men as well as baldness. My fil was taking propecia for BPH.
Did you tell your dr you were on propecia prior to the psa? I think it does alter your psa in some way, although I don't know for sure. You need to let your dr know or ask him.
A.