Prego?

Soo I have been ttc for over 3 years with my SO. I’m currently 6 days late which isn’t a huge surprise as I’ve been late before. I tested with a strip test yesterday and it was negative. I have PCOS but some of my current symptoms (which could be in my head) are cramping as tho my period is starting for a couple days now, nausea but no vomiting, constipation, no period obviously 😂, feeling like crying at every little thing, & when I do small things such as mopping I’ll have lower back pains. Am I going crazy after ttc for so long or do y’all think I could possibly be pregnant and not showing on test yet? I have no idea what I should look for as this would be my first child. Any help appreciated thank you! 💞