u/slothritis

So I have noticed I have started to gain weight since dropping dosage from 15mg to 12.5mg. I hit my goal weight a while ago and i was on the 15 for a few years so i'd figure i would go down and see if I could maintain. However I noticed I've gained a few pounds. My lowest was 133 now 140. How do I know if this actual body fat or just maybe getting used to a low dose. Or should I go back up. Ive been on 12.5 for about 2 months.