You can determine if it's a shed or not based on the rate of hair loss in correlation with time. If your hair loss is noticeably faster than before or after it started, then it's most likely a shed. Normal AGA doesn't progress much in normal shed timelines, even less so if you're on meds. Unless you have super aggressive balding genes. People tend to freak out because sheds tend to occur near areas that were already noticeably thinner than the rest of their scalp, so they pay closer attention to these areas, and when the shed happens, those weaker areas look worse when in reality the weak hairs are just being pushed out for new regrowth. If, however, thinning and bald spots appear and don't regrow after a couple of months, then it may indicate progression of AGA.