How do I determine if I am non-exempt or exempt?

I am a full-time, salaried employee at a 501(c)3 organization in Florida. I do not have a supervisory role. I make 34k/year. Where can I find my classification as to whether I am an exempt or non-exempt employee? I am having an issue to PTO allotment that I would like to get cleared up: My non-profit employer requires me to work outside of my regular 40-hour workweek for special events in exchange for PTO. However, the PTO is not allocated at a 1:1 ratio. For example, I was required to work 10 hours outside of my normal 40 hour work week this weekend, but I was only allocated 5 hours of PTO. If I am non-exempt, I am under the impression, that this is not fair nor legal. However, if I am exempt, then my employer can allocate PTO as they see fit. Please advise. Thank you!