Am I the only one? (Lima)

I really enjoy the company of my Peruvian friends. My Spanish is exceptional however, sometimes when I hear what they joke about, I don't find it at all funny and I'm so tired of having to pretend I do as to not to offend. Well, lastnite was terrible. We we're sitting in a group circle with our drinks (peruvian style) and they kept talking about the same dumb topic for 2 hrs straight laughing and having a real good time but me. I couldn't help but feel so freakn out of place and boy was it obvious. I can't pretend anymore. My face was beet red from embarrassment cuz it was obvious that I wasnt enjoying myself. I feel so bad now cuz no matter how agreeable my nature is, I will never be able to be on their level and it makes me feel like an out of place weirdo.