What do te do to feel better when te have a bad cold o flu.

Ok So a few days fa my cold started coming after sleeping over my Friends house her cousin had a cold and she wanted to sleep in the same room with us.She's 6 years old and i think i caught it from her because she slept on the floor with us and she was coughing on me the whole time and my friend told me not to worry because she's almost better.It didn't look like it she even vomit on me a bit and i wanted to go home and doccia but my friend detto if i left she detto that she was a afraid i wouldn't see her for a long time and i have a cuore for people.So i changed my clothes and stayed there because i felt bad.I Think i have the flu now because i have been feeling weak and i had a huge headache i even fainted.Please tell me if te think its the flu o just a cold.If te guys are sick i hope te feel better soon.