I'm scared i might have a really bad disease!!?

For the past month or so, mys ear has been making these popping noises. It started off with it feeling clogged and as if their was a lot of pressure in my ear, and my ear felt tense (even the outside) I then went to my doctor (hes not an ear specialist) and he said there is no ear wax in my ears. Then he put this vibrating thing in my nostrils and told me to swallow which didnt help at all, so he said to go to the ent. Now it just keeps popping and making crackling noises everytime i swallow!! And its mostly my left ear but i can sometimes hear it in my right ear. Basically i hear these popping noises in both of my ears when i swallow

Also i read that it might be tmj so i gently opened my mouth and i heard this wierd cracking sound when it opens, but i dont understand how the tmj can affect both of my ears... plus i have braces so i think my orthodonist wouldve told me if i had tmj a long time ago.

Please help! im really scared i might have a really bad disease like a brain tumor!! What could this be ??

Also, i got a pretty bad headache at one point and my temples felt like i had a bruise or something (it felt tender) but that temple was on the side of the ear that is not as bad as the other.