Flying back to the mainland US a couple of years ago, (with a head-cold, I might add), both of my eardrums were unable to adjust to the pressure change.
Lots of pain (I won’t go into detail), and some eardrum rupturing occurred.
With a ringing in my ears and some partial deafness, I got in to see an ENT (Ear, Nose, Throat specialist) as quickly as I could.
Her advice for future flights, after thoroughly checking me out-
1) Try not to fly if you have stuffed nose/sinuses (not always possible!)
2) Use a pair of EarPlanes ear plugs when flying
I got my first pair from Bed, Bath, And Beyond (best price- about $5) and used them the next time I flew.
I put them in at take-off, and removed them at landing, and what a world of difference!
They seemed a bit difficult to insert, so the next time I got the kid-size ones. With needle-and-thread, I threaded a tether through them, making removal much easier. (The manufacturers suggest using a pair only once, but I use liquid hand sanitizer to clean them after use, and I’ve had at least 5 flights on a pair.)