Heart problems/volleyball tryouts?

Okay so my volleyball season just stared up again, and I'm getting a tight achey feeling in my chest. I can take a deep breathe. I feel like I'm just sore, but I could be wrong. Any ideas?

ALSO

I'm trying out to be a middle on my JV volleyball team. I'm going to be a junior. There is a sophomore girl who was offered one of the two middle spots on JV or an outside spot on the sophomore team. The other girl trying out for middle isn't very good, but she played our entire sophomore year. I've been playing longer then her but I still feel extremely nervous. I find out tomorrow at 9 AM after a 7-9 AM tryout. Any tips of advice for the final tryout? What is your opinion?
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+1 y
I'm also 6 ft tall, I've played volleyball since 5th grade but didn't get very good until my freshman year. I also played a year of club volleyball but the other middle didn't.
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+1 y
There is also a chance that the sophomore girl could take the outside spot and the other middle and I could be the middles, but I don't know what the sophomore will do.
Heart problems/volleyball tryouts?
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