I had sex on Oct 22, LH surge was positive on Oct 26 & 27 which I think that means I would ovulate by October 28th? (I ovulate later in my cycle). I “thought” I got my period around the normal time (I spot for a few days prior to bleeding). Spotting started on time on November 6 and finally had a ‘flow’ on November 11 (it was more brown medium watery bleeding that filled a pad for two days, seemed different). I assumed this was a period and didn’t take a pregnancy test.

I had sex on November 21 and 23. I don’t know when I ovulated this cycle (took tests Nov 19-22 that were negative but stopped taking them after that). I could have ovulated the 24-25 based on my late ovulation timing. I was supposed to start my period on Dec 5 and I again thought I did, I had spotting (which is normal for me) but a flow never came so I took a pregnancy test on Dec 8 and it was positive. I had similar brown bleeding again throughout the week.

I still have a gut feeling I conceived during my October cycle (because I was spotting this month too, I wasn’t certain I really got my period in Nov).

Because I wasn’t sure, I went for dating US on 12/18 and there was no fetal pole, but 10 days later on 12/28 a heartbeat was detected (154) and they said I was measuring 6week6days. I went to my first Dr appointment this week (based on dating I’d be 11 weeks) and I was told I won’t get another US until 18weeks because they go with the date I got early on. I’m concerned because I’ve read that early ultrasounds can be off, and this was very early on, but can they be off by a cycle?

The dates given early seem to match with possible conception in Nov, but I don’t know for sure when or if I ovulated. I can’t shake this gut feeling, but if I ovulated on October 28 I would have measured farther along, right? My October period began on Oct 9 with spotting and more of a flow on Oct 12 and ovulated late on Oct 28 (about day 20 of cycle). Is it possible that this pregnancy began in October?

Can anyone ease my mind. Based on the dating I should have conceived during the November cycle and I want that to be the case, but have a weird feeling. Has anyone else had this happen or should I just let it go and trust the US date? I’m anxious, it’s my first pregnancy.