ADVICE NEEDED

Hello so no judgement please I just need advice right now. So I have struggled with an eating disorder on and off for the past few years and recently it hasn't been that great. In the past when things were bad my period has gotten irregular and has also stopped coming all together. Now, my period is 4 days late, but me and my boyfriend also had unprotected sex two weeks. He pulled out and I know that this was a bad idea. I completely regret it and won't ever do it again. Right now I don't know if my period is late because of my eating disorder or because I'm pregnant and I'm not really sure what I should do.