Negative tests, no period, could I be pregnant?

My period usually lasts about 30 days...I’m currently on day 44 with consistent spotting over the last week. It started off tan and then a dark brown, but now it’s mostly pink and occasionally red.
I’ve taken 3 pregnancy tests and they all say negative and normally I’d accept that, but this is just irregular for me, especially since I haven’t had my actual period. I unfortunately don’t know whether I ovulated or not as I have not been doing testing.
My breasts are heavy, swollen and tender and I’m having off and on nausea.
Could I be pregnant or are my body’s hormones all out of whack? I’m so confused!