10 points for best answer, I don't know if i should say this to my gf?

Tell her "I think, I'm falling in love with you". This is like a step before saying you love her. You can follow it up with a couple compliments on why you feel that way. Like " Because, you are so easy to be around and fun to be with" or because " you make my day everytime I am with you". She may surprise you and tell you she loves you. But if she doesn't say anything back, don't feel rejected. She may just be caught off guard and she may not know what to say. Its how she acts after you say it. If she seems upset then apologize and tell her you didn't mean to freak her out. But more than likely, she is going to say it back, or she will kiss and hug you as a sort of "thank you" for your sweet words. I think you will be okay :)