Advice please!

UPDATE! Everything went perfect baby only would move into a good position for pictures once lol definitely was being lazy! He or she lovesss my left side right over the cervix lol heartbeat was 176 and everything looked perfect the doctor said! The doctor was able to easily get the heartbeat on their Doppler too which he was shocked he found so easily so early on.

So I have a fetal heartbeat Doppler and have been able to find the heartbeat with ease the last 2 or 3 weeks. I heard it yesterday clear as day. Today I have my 12 week scan appt and my crazy self decided to use the Doppler again. I couldn’t find the heart beat. I’m completely freaked out and praying the baby is just in a spot that can’t be picked up right now. My appt is in 2 hours but now I’m so stressed. I know there is a lot of people who are against them and also those that find it one day and not the next. So I’m just asking for support has anyone had this happen and everything turned out ok? I had a miscarriage in February and have been so scared this entire first trimester.