Ktking---You're likely having a mild dose of OHSS, the pregnyl makes it worse. On the other hand, it can be a sign of BFP, as the hormone level goes up hence making OHSS symptoms worse. I get that only with BFPs. Drink plenty of water, have plenty of proteins and rest. If it's still bad maybe ring Wazza/Kate, sometimes he advises halving the dose of next pregnyl booster or omitting it.