Bleeding early 2nd trimester

Hi,currently l am in my 14th week of pregnancy with twins.Bleeding started with cramps on my 13th week.Rushed to ed but thankfully cervix is closed and the two babies are doing fine. Subsequently,now only brownish discharges and cramps no more. My gynae told me its normal.It might last for a while but some may have it til the end. It is still worrying even though he said its normal.Cos I never had any bleeding with my other singleton babies.Just wondering if other mommies have the same experience while having twins. And to be wearing pad all the way will gives me nappy rash. And another worrying thing is,I am so afraid to defecate,so afraid that I pushing babies out instead. I guess I am thinking too much...