Joining the military??

Kylie
Hey ladies! I decided to post this conflict on here because this is an all women community and I figured I would get the most honest answers.
I am going on 19 years old. I did extremely well all throughout high school. I've been in college for the past year but I have absolutely no motivation to go to classes and I am failing miserably. I know that I want to do something with my life but I don't know what and time is ticking. I am going stir crazy living with my parents and they love me but they want me out too, lol. 
That being said, I am thinking of joining either the Air Force or the Navy. I'd like to know if any girls have a similar experience/experiences in either branch! Which is better? Pros and cons? Etc. 
Just a few facts about myself if it helps:
I am a small girl. 5'4, 105 pounds. 
I have fears about leaving home because I have social anxiety. I'm also scared about what my boyfriend will think but I have yet to talk to him. 
I also do not exercise regularly as my metabolism is extremely fast, and I love chicken nuggets. 
I literally know nothing about either branch! I'm going to talk to recruiters but any honest outside information helps!