Why is my ear doing this?

I recently dealt with a nasty sinus infection. It finally went away, but now my ears are bothering me.

Every time I blow my nose, my left ear pops and I have the most excruciating pain in my ear for a few minutes. It is also slightly clogged.

Why is my ear doing this and what can I do to fix it? I’d really like to blow my nose without crying every time.