HELP WHAT IS MY BODY DOING

Dr
Okay so I missed my period last month, I had a light one one in between the time i was sexually active in early February but I was like 3 days late the last time I had sex. 
We used a condom and as far as I know, it didn't break. 
18 days later, I think I finally start when I see a little bit of pinkish/red. It never got heavier and eventually turned into a light brown and lasted until the next day. 
Today I woke up and no more spotting, but watery discharge. 
What. Is. My. Body. Doing?! I don't know if I should worry that I'm dying or go on with life. 
I can't switch insurance until I'm 26 so I'm still on my dad's until the fall and i live in a different state and haven't had time to make a trip home to go to my gyno so I wanted to see if anyone has ever experienced anything like this before and if it's cause to worry and make a trip back or just chalk it up to stress.