Please help! Really need an advice.

So me and my boyfriend had sex and the condom broke (this is was Wednesday which is the 27th) He finished in me and we actually found out about 10-15 min after that. Now on this app it said that i am not in my fertile window, but i am super irregular and my ovulation cycle in never according to the app or the way it is supposed to be. It has been four days so far and i have gotten a few different kinds of discharges and i am so worried. When would be the best time to test? I took a pregnancy test yesterday but it turned out negative. However i read that my HGG levels would not be caught so early on.