I get some cramping with fina. The worst is right between the legs when you are taking a piss. Shit that hurts like hell. For those taking clen, that could be your problem. I usually get no sides from clen but when I don't taper up, the first 2 days are un-fucking-bearable cramp-wise. I had that same ab problem but it was my lower right one and it was scary as hell and hurt like a bitch.