Beta levels help please

So last week I found out I was over a month along. I got bloodwork taken Friday and my beta levels were 33 then on Tuesday they tested again and they were 147.4 now that tested on Thursday and my levels were 275. So they didn't exactly double which is making me worry. My doctor is ordering me an ultrasound to see if it's ectopic, though I haven't experienced any bleeding or any pains other than when I need to fart. I need some reassurance.

What were your levels they aren't sure how far along I am due to irregular periods, they estimate around 5 weeks. I'd really appreciate your help