As you are learning, taking "meds" for what is bothering you is not a perfect solution. They all have side effects. Sometimes the side effects are worse than what you're treating. Then your body will build an equilibrium (resistance) to the medication forcing you to take more. Then it's really rough if you have to come off the medication for any reason as the rebound (a.k.a. withdrawal) can be brutal.
Adding more medications to treat the side effects is a bad idea too.
Your life starts to revolve around making sure you have these pills with you. Business trips, vacations, going out for the night, all become a pain in the rear as you are always making sure you have this medication around.
I've been down this route myself and learned it all the hard way.
You are young and still growing, way too young to start taking a beta blocker for something that isn't an issue. Your heart rate is going to change over time, if you're medicating it you will lose this. By the time you're 25 it'll be different but if you are taking a beta blocker who knows how this will evolve. I didn't stop growing (muscle - wise) until I was 27.