should be fine. unless you feel aburning sensation and your eyes keep tearing. otherwise i suggest you wash your eyes clean with some mild anit bacteria soap or foam, cut a cucumber and let it rest on your eyes.
ive had tank water i n my eyes and even accidentaly drank some whiles syphoning dureing water change, it may not taste nice but its just water, dont worry about it. your eye twiches could simply be a spasm or due to stress. Now, if you had medication in the water and you got some in your eyes then simply get in the shower, hold your eyes open and flush them with cold water.
eye twitching that is not accompanied by redness, swelling and itchiness is usually just a sign of stress. So get off the computer/video games/porn/TV etc and relax and it should go away. Also most colleges have a free health clinic and offer cheap insurance. If you are actually poor there is always medicaide which is free and about the best health insurace out there.
If you are worried about the flesh eating bacteria you should probably sacrifice the eye to save the rest of your body. Popping out the eye with a teaspoon and cauterizing the socket with a soldering iron is probably your best bet.