A bump in my mouth?? Ok for an airplane ride?

I am flying on a plane tomorrow (jan 7th) from TN to TX and I am very worried about my mouth. I have never had good teeth, no matter what I do, I always have a cavity or something. About a year ago I got two bumps in my mouth. At first one was just a bump. It didn't (and still doesn't) hurt when I push on it but now sometimes it gets filled with a p***y type thing and will pop if I push on it. It still doesn't hurt when that happens but it really worries me SPECIALLY since I will be on a plane tomorrow. The last time I flew I had a root canal that I didn't now about and I was in tears, borderline freak out, for the last two hours of my flight. It was worse than both my child birth's and I don't want to encounter it again. I tried to get into the dentist but with my husband's job basically never lets him take time off (I've had to reschedule 4 times already and just finally gave up lol). Does anyone know what this could be?? I know it's nothing good since nothing good ever happens to my teeth, but I really just need to know if I should take a c**p load of pain killers for the flight tomorrow or not.