Don - u go to ur gyne as many times as u want - if thats what it is going to take for you to relax and enjoy ur pregnancy!!!! - dont do what i did and stress the whole time as u wont enjoy it as much as u shld and than u might end up regretting it - It goes all too fast! but i do understand over anylising everything!
Do what ever u have to do to put ur mind at ease! but meanwhile have some fun and try and relax! xoxo