Have you taken your body temp. yet? If your feeling nothing and it's not increasing your body temp, I'd just go off of it. If you purchased it from where you said you did, I wouldn't question if it's fake or not. The highest I've gone on clen was 200mcgs a day. This is a very high dose that was broken up into 4 times a day at 50mcgs each. IMO, 160mcg's at one time is NOT a good idea! Your body temp might be elevated at 40 to 60mcg's and you may just not be feeling the sides, and your taking 160mcg's all at once!! Check your temp out before taking doses that high.