Laura,
Draining from the ear would indicate a ruptured ear drum from the pressure not being able to be relieved through the eustacian tubes. Fluid buildup is quite common post radiation because of damage to the eustacian tubes. You might also have an infection. I would see my ENT over this.

I couldn't tell whether you were kidding or not but you shouldn't be putting water in your ear, or Q-tips.

A ruptured ear drum can result in mid range hearing loss, depending on how it heals up.

Hard wax buildup typically dose not cause pain. Like Cathy, I have hard wax buildup on the side that was radiated, I just have them remove it at every followup visit - no big deal takes a few seconds.

I had ear pain for a month or more post Tx.