water spill in back of MacBook

Clumsy me, knocked a glass of water over behind my MacBook as i was moving a cord. Some of the water did go into the back of the MacBook i believe, as well as the whole bottom of it was wet, and the display went off right away. I dried it, and tried to power it on. It did turn on, and not knowing i was not supposed to plug it in after water spillage, i plugged it into my Thunderbolt display. The display worked fine, but after a while, the MacBooks display shut off while the display on the Thunderbolt stayed on. I've had my macbook upside down like other guides said to do, and drying in front of a fan for the past day. I did get curious (I know, dumb) and turn it back on and its fine. It turned on fine, and everything's working the same and the display hasn't shut off yet, as I'm typing on it now. Im wondering if there will be signs later showing water damage? I haven't had any problems turning it on thus far. I'm scared that it'll just stop at some point, so what should I do? I realized after this happened that AppleCare doesn't cover water damage, and just being a waitress, and a college student, i can't pay for Apple to fix it. Please help!