What’s going on?

I have a few days before my period is suppose to start per Glows calendar but today out of nowhere I felt dizzy and nauseous. I currently feel like I have to puke but as I sit by the toilet I’m just gagging. For the last 2 weeks I have been a serious bitch to everyone and irritable from anyone I get in contact with which is so wired and not normal for me. I had my period in the begging of this month. What could this be? Me and my husband have been trying to conceive so not sure if its too early to tell or I’m trippn please let me know.