Advice?

Hi everyone! It’s me again. A few days ago I wrote on here talking about how I am several days late on my period. I also talked about how I took a Plan B at the beginning of all of this and how I know a bunch of the symptoms I can be feeling are from the plan b. I’ve taken 3 pregnancy test during all of this and they’ve all come up negative. I am now 11 days late and my boobs are extremely sore, like it hurts to even press down on them. They might be sore from my boyfriend play with them lol because he can’t be a little rough sometimes . But I’m so worried that it could be something more than just that. Ive also felt kind of nauseous again lately but a little more nauseous then normal. I don’t know what to do and I’m getting anxious all over again please help.