Feeling Left Out in Math Club

I joined the math club because I thought it would be cool to bond over equations and numbers with like-minded people. But every time we meet, they talk about calculus and advanced algebra stuff that flies right over my head. I'm more into geometry and basic trigonometry. I feel so out of place and left behind in these meetings. Should I just pretend to understand or try talking to them about what I do get? Is it okay if not everyone in a club is on the same academic level?