Pregnant after told I don't ovulate

I had my son (now 2) using clomid.. there were originally 2 babies but the second was smaller and was gone by 10 weeks, my other son is completely healthy. Also I have been told I have pcos, a dr looked at my ovaries before my first pregnancy and told me that. We decided to start (not actively) trying for #2 in February when I got my non hormonal iud taken out. Ran a marathon in may then decided to get progesterone test to see if I am ovulating this past month, last pregnancy I was told I wasn't. This time I was told my ovulation levels were 9. So I agreed to start clomid again. I waited for my period to come and it never did. I took two pregnancy tests and saw I'm pregnant. We go to California for a vacation every July and my dr thinks I got pregnant bc I am so relaxed looking forward to it-bc I got pregnant with my son the same time 3 years ago. Anyways I was shocked when I found out I was pregnant so I called the dr and got a blood test. She said hcg levels were in the (2000's I think) good but my progesterone levels were low (only raised to 10.2 two weeks after original ovulation test). I am now taking 200mg every night. My dr said her concern is there may only be a sac and no baby.. I know everything is meant to happen but now I'm on vacation and having a hard time thinking about anything else other then whether the progesterone is helping and what is going to happen at my ultrasound when I get back.. anyone have this happen and have a successful pregnancy? I'm so scared to enjoy the fact that I am pregnant just to go in the office and be told it's no good.. every day that goes by makes me worry more and I'm trying so hard not too. This was the last thing I expected getting pregnant on my own but it's the best and most exciting too. I know my hormone levels are whacked right now bc I am almost off the charts crazy, and super tired and hungry, at times nauseous--but it's also hard to figure out if it's just mental lol