Syringing, hydrogen peroxide, antibiotics, decongestant, ear spray

Hi,

I have had a muffled left ear since December, I went to the doctors who prescribed me an ear spray to remove an outer ear infection. i was also using hydrogen peroxide.

In February, I had my ears syringed which a little ear wax came out. The following few days I had the worst ear and jaw pain so used antibiotics.

My left ear is still muffled and whenever I try to hold my nose and blow down, the left ear will never pop open.

I assume there is an issue behind my ear drum?

Does anyone else have any advice, I’m only 24.

thank you