Due Date Help

Lauren • Jace 💙 ✨Livvy 🎀✨PCOS Warrior 🏹

I would just like some thoughts please. My last period was on December 13th. I did not have a period at all in January, but I tested when my period was late in January and didn’t get a positive. So I let it go and didn’t think to test again until Sunday, because I just felt off and was surprised to see a positive pregnancy test! I’m so excited, but a little confused. Would you go by your last period? I have an appointment set up for the 13th of this month and I know I’ll find out (hopefully) for sure but I’m just curious.