Thought I was 7w2d but...

Went for my first ultrasound today and I am measuring 5w5d instead of 7w2d and there is no baby or yolk sac to be found. I have a messed up cycle and wasn’t expecting to conceive as I was waiting for my period to start so I could start taking medicine to increase ovulation; we don’t have an exact time of ovulation. This is so frustrating!! At the moment we’re playing the waiting game and I have another ultrasound scheduled for a week and 4 days from now to see if there is anything there. Anyone else have this happen and you were still pregnant... with an actual baby in there lol? The only pregnancy symptoms I have are fatigue and frequent urination; my boobs stopped hurting a week ago and that was my only other symptom besides the other two listed above. I’m at a loss and so disheartened by this news. I definitely need some prayers over here 😕😢