Am I allowed to be annoyed.

I'm currently trying to conceive baby number 2. It's already proving harder than the first and I'm loosing it. My best friend just told me she's pregnant and it happened by accident. I'm so happy for her of course but I'm annoyed aswell and actually really devastated cause I just come on my period aswell. I want to cry and desperately needed to let that out and hope that someone can relate.