I feel pregnant but I'm not. So what's going on with my body?

So first day lof my LMP was October 14. We had sex October 28th and twice the week before my last period. I am supposed to get my period in 7 days from today per Glo. The past 4 days I have been feeling different in my stomach. Idk how else to explain it but its 100% not period or menstrual oriented. So it noticable as feeling "different" and same with my boobs. But nothing is over the top symptoms it's very subtle. So I took like a million pregnancy test last night at 6 pm and one deff gave a faint line. This made me to to a patient first and get the blood test. It came back negitive. I really wasent expecting that... so anyway here I am today still feeling my stomach saying wtf. If I'm not pregnant then what's up with me. Or is it too early for any test to really pick up anything since I'm still 7 days out from my next period. Help! With all your advice. Ps. We are not ttc but we did just get married in July and and just living life so if pregnancy were to happen we would be ecstatic. Thank you in advance for your help