Why Am I Already Out Of Breath at 10 Weeks?

I heard further along in the pregnancy you can get out of breath because the uterus gets too big to fit in your pelvic region so it moves up and squishes your abdomen which presses against your lungs, but I'm only 10 weeks! Isn't it a little too early for this? At my first prenatal appointment I also had high blood pressure(which I never have had pre pregnancy) and the nurse said I probably was just excited but now I'm worried I might be getting hypertension or something. Has anyone else had this?