Worried Sick

I am terrified of having a missed miscarriage. I will be 11 weeks tomorrow. My next ultrasound is the NT next Friday at 12w2d. I have already had four ultrasounds: 5w6d, 7w6d, 9w4d, and 10w. The baby measured correctly and had a great heartbeat at every single one. This is my first baby and I am just scared in the last couple weeks of this trimester that something will go wrong! Anyone else feeling this way? :(