Blocked Ear When Inhaling During Exercise

So today, for the first time in about 2 years, I decided to go gym with my friend. He's pretty good at it and I think he was pushing me (which I think is good!).

However, after about 30 mins, I would realise everytime I would inhale that my ear seemed to spaz out and become 100% blocked. Literally deaf in one ear. It went away shortly after I sat down. However it REALLY freaked me out.

My question is, is this just another tinnitus reaction I will have to learn to deal with? Or should I stop gyming?

P.S. I am about 8 months in.