Pregnancy after mc..

Kiley • Pregnant with rainbow baby! ❤️👶 due date April 20th!
So I've taken like 5 pregnancy tests and I've gotten all positives, they have gotten darker which helps to assure me that my levels are rising. I have my first appointment on the 18th where I will get my blood drawn to make sure everything is looking good. Calculating from my first day of my last menstral cycle, my due date would be April 20th and that means I'm about 4 weeks. I'm worried and can't help but remember that my miscarriage happened at 5 weeks just two months ago. 
Any advice? I'll do anything to make sure this one sticks.