am I pregnant!?

so far I am 13weeks late one my period... I'm already irregular but usually get something every month wether it's spotting or my full fledged period, and it's been nothing for 13weeks. I've taken about 4 home tests.....all negative, so I spoke to a nurse and did a blood test....negative again. last week I had an appt with my regular woman's health Dr and he did some hormone tests, all normal. now on the 25th I have an ultrasound to look at my uterus, am I insane for thinking somethings glitching somewhere and I'm finally pregnant....im just so tired of getting my hopes up and being let down....its been 3yrs.

I forgot to add I've been feeling really off the past couple weeks. at work I do a lot of lifting which is usually no problem and lately it's been a bit of a struggle, I've been extra sleepy and hungry, my backs been in more pain than normal and I've had headaches galore.....