Cramping stopped

Hello! I’m 3 weeks and 6 days pregnant and up until now I’ve been having cramping in my uterus. Today they were less severe and I tested twice yesterday first time at 12 pm and second at 11:40 pm. I received a stronger line with FMU but I noticed my line faded when I took the second test. My lines are usually darker in the evening or the same darkness as fmu. Now I’m worried and I’m breaking at the thought I’m having a chemical.

This is my first pregnancy and I can’t stop stressing about if I can carry to term without having a miscarriage. I thought my stress would alleviate when I got my bfp but it hasn’t. Before I worried about getting pregnant now I’m worrying about staying that way. I’m 15dpo and tested both times at 14dpo.