Early pregnancy and terrified

I just found out I was pregnant after trying since September and while I am so excited about it I am also finding myself obsessively worrying about miscarriage. I found out super early (I’m 4 weeks now and 13dpo today is the first day of my missed period) and idk. I keep feeling this absolute knot in my stomach that it’s not actually happening and it will end in a chemical.

Also I was only able to make an appointment for 10 weeks out and idk it feels so far away and I’m worried if something is wrong I’m just waiting to be devastated.

What is going on? Has anyone else felt this kind of nervousness this early? Am I crazy or something? I just so desperately want this and am so scared it’s gonna end too soon.

Side note!! I’m on a medication for adhd that other countries outside the USA have very thorough studies on with the conclusion it’s safe. In fact I quit taking it for a few months and my doctor told me to get back on it before this last cycle and here I am pregnant.