Spinal muscular Atrophy HELP!!

I got a call this morning from my nurse saying I tested positive as a carrier for SMA and I’m freaking out she said “ but I wanna hold to worry everyone tests positive for it” which I find really hard to believe up until now I never heard of this and now I’m scared my baby will have it.

I have an appointment March 22 (a month from now) with a specialist to make sure the baby is ok but now I’m terrified has anyone else tested positive as a carrier? Or know any information about this disorder? I’m honestly so worried right now this is my first pregnancy.....Help!!!