Gender Ultrasound Tommorow

So tommorow I find out the sex of my baby , I was so excited counting down the days and don't get me wrong , I still am but its just that i'm just worried now :(  I'm 18 weeks today , I just worry because I see the posts of othet girls on here saying they lost their baby and it's so sad like this baby is all i've ever wanted and I don't want to loose him/her I hope my baby is healthy and still has a heartbeat ❤️ I haven't had any bad symptoms like bleeding or etc. Idk maybe I worry because I have no pregnancy symptoms other than sore breasts , and my belly has grown but not much and I haven't felt my baby move but it's my first baby. 
can anyone relate or give me reassurance ? wish me luck ladies !