Feeling anxious

Laurel • Chemical Pregnancy, Miscarriage at 8 weeks, healthy rainbow baby girl January of 2016, miscarriage due to abruption at 13 weeks currently pregnant again
So I am 13w3 after a miscarriage at Christmas at 8 weeks. We have seems the baby at 6w4, 7w1, 8w5, 10w3, and 12w2. Every time baby has measured right on track and at the 12 week scan baby was jumping around, dancing showing off doing flips etc. heartbeat has been great at all. The past 2 days I have been feeling worried that when I go in for my next appointment there won't be a heartbeat. I know it's a tiny tiny chance of something going wrong at this point and my doctors are all very optimistic that everything is good. All my blood work is normal everything is the right size and measuring good I'm not sure where the worry is coming from. I guess I'm just looking for some reassurance that it's just my hormones going crazy that I'm feeling like this. I still have my fatigue and my sore breasts and my appetite has picked up and I'm still having bad pelvic girdle pain. Just looking for some reassurance. Thanks.