Hi Rachel: I have posted (or basically, re-posted a long thing I wrote on flying awhile ago) several times, because this question keeps coming up. Its a biggie for me, as barotrauma that happened during a long air flight caused my tinnitus. I have high-frequency T, not low, but you mainly want to protect your ears from the noise (which isn't overwhelming, but enough to require some protection.) Its usually quieter towards the front of the plane, if you have a choice.
Also, sounds like you have pressure/pain issues with your ears, as I do/did.
If you are worried about eustachian tube dysfunction, have what is called a tympanic test from an ENT within a week before you leave. Will show if your tubes are working properly.
And you can buy Earplanes at any drug store, or even at airports (although I would get them before I went to the airport). READ THE BOX first. There are very specific instructions on when to put them in and take them out. I used mine on the both the ascent and descent. Also, be aware that Earplanes will give you some protection from noise... about 20 db. But you will be more comfortable if you take them out at cruising altitude and put in foam plugs.
Here is the rest of my original post:
There is an extensive thread already here at TT on flying:
Flying: https://www.tinnitustalk.com/threads/flying-tinnitus.1001/page-2#post-21420
FYI: I flew recently and was scared witless, given I got tinnitus through barotrauma on a long flight. Robert Fahey, on this thread, gives a great piece of advice that I followed: Keep your mouth WIDE open during the descent, as it forces open your eustachian tubes. Yeah, you look pretty silly. You can explain what is happening to the person sitting next to you or not.
Also: I went to the ENT a week before my flight and had both my E.tube function and my sinuses checked, to make sure I didn't have a hidden infection. I then dried my head out completely with Sudafed (decongestant) beginning 36 hours in advance. Dose yourself per directions on the package (I took one pill every 12 hours). Then, I used Afrin nasal spray about 30 minutes before take off and again as descent began.
And: I used Earplanes plugs, as someone else here suggested. Follow the directions on the box; read them in advance. You take the Earplanes out when you reach cruising altitude and then can pop in foam plugs and/or use noise cancelling headphones to cut the noise from the plane. Put the plugs back in about 30 minutes/one hour before descent. Again, follow directions on the box. However, I think it did say to put them in an hour before descent, which doesn't make sense on a short flight. My flight was two hours and I put them in about 30-40 minutes before descent. Do not take the Earplanes out until the plane lands, is at the gate and the cabin door is opened, which is when the plane will completely equalize. Don't freak out if your ears hurt while the Earplanes are in... they are just a little uncomfortable. If you have small ear canals, like I do, buy the ones for kids.
Finally, if you really are freaked out about flying, consider asking your doctor for just a couple anti-anxiety meds to calm you down. A .25 mg Xanax did it for me; it's not enough to knock you out and asking for only two pills, one for the flight over and one back, should not cause the physician any worries. Or you, for that matter. Or if you are a natural meds person, find a natural relaxing supplement.
By the way: The above routine might be a little more than you need if you are not pressure sensitive, as I am. But I will tell you it worked for me.