Using Child Ear Plugs, Pain In The Ear. Damaged Membrane?

Hi, I think I have damaged my right ear. I bought child earplugs from the shop after finding the normal ear plugs uncomfortable. I pushed the small child earplug too far into my right ear and it went right in. To take it out was quite a struggle. Now my ear is highly sensitive to what appears to me to be any sort of pressure change in my ears, a small hiccup for example is extremely painful and so is putting my finger in my ear. I am sure that I have somehow damaged the membrane of my eardrum or something, either when pushing it in or pulling it out (it was those rubber earplugs that could cause a suction when pulling it out). What should I do, what shouldn't I do? Should I avoid letting water get into my ear for example? How long can I expect it to take to get better?