Possible heart problem.. Scared 😞

I'm 17 years old just got out of hospital a few days ago after spending about 12 hours in there as I had a panic attack and that triggered an asthma attack and at resuscitation they gave me a load of drugs that they even said can increase my heart rate as it was at 139 but settled right down to 100-110 when they discharged me and I was obviously panicking a lot.  However my mum spoke to my asthma nurse today & she wants to do a load of tests on me as she thinks I may have a heart issue but it's a process of elimination she said.  im very scared like so scared I've got so many things running through my mind like what if I do? How bad will it affect me and will I live long ? My grandad suffers with a chronic heart disease but there's no proof that that is genetic. I'm just terrified. I think it could just be due to the fact my heart was fast as the drugs they gave me increased it and I was panicking so that also increased it but my mum has really scared me with this :( any advice I'm really worried and I'm anxious as it is