Preterm labor or am I crazy??

I'm 34 weeks tomorrow, and also have a doctors appt tomorrow where I'll be asking about this.

All of a sudden starting Monday morning I've had a lot of pressure pushing down, like baby has dropped and it's harder to walk now. Since yesterday I've had constant lower back pain, worse today and I can barely stand without fidgeting everything hurts. I've also been feeling crampy, but only maybe twice a day for a few minutes and random bouts of nausea.

Baby seems to always be pushing out on my stomach now, making everything feel very tight. I've also been running to the bathroom more (if that's possible). I haven't had any issues my whole pregnancy, I'm a ftm and no Braxton hicks. Just curious because all this has just started happening monday