Found out I’m expecting… at almost 30 weeks.. so confused and stressed.

okay for starters this is going to be a bit long, but I could really use some advice/ knowledge. I went to the er a couple nights ago, thinking I had a kidney stone (turns out I did). But what I wasn’t expecting to hear is that I’m almost 30 weeks pregnant…. Some backstory: I’m 23 and weigh about 225 pounds. Had intercourse ONE time about 8ish months ago (don’t really recall the exact time frame) so that could be a little off. About a month and a half later I went to er because I was having severe pain in my stomach. They did a CT scan and ultrasound (TV and standard abdominal). To see what was going on. Turns out I had I had an ovarian cyst rupture. (I have Pcos btw). But I’m mentioning this because when they did blood tests/ the other testing there was no sign of any pregnancy (not that I or the doctors thought I was pregnant). And pregnancy test is just routine for blood work they do. And that was negative along with urine. But keep in mind I must have been about a month and a half pregnant at this point.. I went home the next day after going to the er with just the diagnosis of an ovarian cyst rupture. The next few months I got a “period” every month. But they’ve always been irregular due to Pcos. Sometimes I’d get really short cycles (about 18 day cycles) and one time it was a 38 day cycle. But I just figured it was cuz I’m irregular. So fast forward to a couple nights ago when I went to er for a kidney stone (I was almost certain I had one cuz I’ve had 2 before and it felt the same as the other times). They did normal blood work and urine and once again NEGATIVE pregnancy test on Both. But when they did the ultrasound (didn’t do a ct this time) they told me I am around 30 weeks pregnant…. But before the doctors told me The technician doing the ultrasound I guess didn’t know my blood tests and urine test were negative for pregnancy. So she asked me why I wasn’t in the ob ward (I think that’s what it’s called). And I told her wait what? I’m not pregnant? And she laughed thinking I was joking. And then realized I wasn’t. So she quickly changed the subject and said the doctor would talk to me. And when the docs came in they literally said “soooooo we are a bit puzzled because you have negative hcg tests both urine and blood but you are clearly pregnant). And I just don’t even remember after that. I told them things like “but I get my period” “I have no symptoms” and all that stuff. And they really didn’t have any knowledge to give me and said they would refer me asap to an obgyn and they’d have more knowledge. My appointment isn’t until Wednesday (Feb 5th) but I’m honestly just so anxious and confused and want to be seen like right now. (Which I know I can’t but ugh I am just stressed). Does anyone on here have any advice/ knowledge about this? The only “symptoms” I had/have is weight gain. But my weight always fluctuates with pcos. So I didn’t really think anything of it. But now thinking about it this is the heaviest I’ve weighed ever. The heaviest before all this was about 190. But it’s not like I have a bump it just looks like chubby/ flabby stomach. I am so anxious because I have been taking my medications every day and idk if they’re safe for a baby (focalin, vraylar, lamictal, cymbalta, and spirnolactone (for acne)). I also vape every day (which I havent since finding out this news). I don’t feel prepared at all and this is all happening so fast. I don’t understand how all my tests were negative and I still got my period (which I guess isn’t a period but what is it then??) Just so confused and stressed. If you have any advice or know how this is even possible please let me know. Thank you! And I’ll update this post after my appointment on Wednesday. Update: had my appointment yesterday! It’s a girl!! Measuring at right around 32 weeks. She’s healthy! They didn’t really give me any definitive answers as to why it all happened this way. But Im so relieved that baby is healthy! Just need to prepare quickly haha. Thank you guys so much for your support!!! It means a lot 😊