Help...

So recently I had some unprotected sex and I’m not on birth control so I took the morning after pill. Strangely enough 5 days later I bled some, kind of thought it was my period but it only lasted for two days. The first time I took the morning after pill the same thing happened. Im not sure if that’s a normal reaction for some people or what but I went with it. However, I am now 14 days late on my period and I’m a little concerned if the pills worked. I did take a dollar pregnancy test last week and it was negative but I know there can always be false negative and all. So I’m just looking for some advice or info here. Like does the pill mess with your period this much and maybe I should just wait it out, or should i go take a pricier pregnancy test, or what?

I’d appreciate any help or advice, thank you.