Hi jprincess! :)
i have exactly the same problem as you. I am 21 and I also get chest pains, mine come about 7 or 8 times a day/night, the pain is quite a sharp achy pain and it also goes down my right arm it in my shoulder and my hand, my hands ( both go numb and fuzzy), I think the reason it makes your heartbeat faster and you feel dizzy is because like me you panic about it being something bad? Next time the pains come just try and breath slowly that’s what I do most of the time.
Also like yours my pain comes at all times, even when I am relaxed, happy, watching tv ect.
I went to the doctors a couple of times ( this has been going on 3 month) and he also said to me, your 21 its not likely to be your heart, he diagnosed me with anxiety and gave me some tablets. I’m still worried though and think its something more. I don’t think the doc take me seriously.
We are probably (hopefully) worrying about nothing, reading through this forum had helped me over the last few days, made me think maybe it is anxiety after all. I will go back to the doctors if it carry’s on as there is always them 'what if's'