Why do I feel dizzy, and wheezy after 5 years of being on Propranolol?

[MP7]

Im a 21 year old male, when I was 16 I was found to have social anxiety, low blood pressure & also an irregular heart beat.  i found myself unable to attend school assemblies etc my social anxiety was so bad, helped not by my other underlying conditions. Even tho I am asthmatic I was put on 40mg propranolol daily, it changed my life, I was able to queue up in public places etc without the fear of fainting. Anyway 5 years later, 3 weeks ago I experienced sleep paralysis for the 1st time. I suffered the hallucinations and died basically then fully woke up. I was a little shaken but the rest of the day I had dizziness and palpatations, of the kind K had before being on propranolol. I ended up at the out of hours doctor who basically laughed it off and played the ‘anxiety’ excuse, the next day I went to my GP who thoroughly looked into all the scans And ecgs I had in 2013, which were of no concern, he wants me now to see a cardiologist. 3 weeks later still not letter from the hospital. Im a uni student and In these 3 weeks i cant attend lectures everyday my head goes faint iv suffered minor blackouts, im still having palpatations daily 3 weeks later and somedays my asthma gets my chest tight so i grab my inhalor. I cant queue anymore the dizzy spells are worse than they were in 2013 I almost feel like I am going to drop dead, have a heart attack or asthma attack, tt scares me I am a healthy 21 year old lad.