Monthly appointment in the morning and nervous

C
My last appointment was feb 1. Baby was healthy but I am 18wks haven't gained weight, haven't had sickness, no cravings or any movement. I don't know what it should feel like to be pregnant but however it feels I don't feel like I am. Plus I feel so bad cause the last couple of weeks I either have coffee or soda and on some days both.
I've been reading so much about missed miscarriages I freaked myself out and now I am scared to go to my appointment in the morning.