Girl cum

So my boyfriend and I are always careful when having sex , I'm on birth control be we still use condoms , well today we didn't use a condom and when we were about to switch positions he noticed a lot of white fluids coming out from my and he looked really concerned and confused and I asked him if he cummed and he said "NO? " he was really confused because of course he would have known if he cummed ... so then we assumed it was my cum .... should I be worried or should I go along thinking it was my cum ? It was also very different from sperm , to me it looked more like milk like creamy discharge ... whereas his cum seems more watery and not as thick as mine