<human>: Last night my girlfriend and I were sharing a bed, and it ended in lots of physicality. Near the end of it, my girlfriend whispers to me the words "I love you". Now, I like her a lot, but I'm not in love with her yet (we've only been dating for a month and a half). I didn't say anything, and though It won't affect our relationship or my reactions to her, I'm unsure of what to do if she says it again. What should I do?

NOTES: We are both 18 years old, in high school, and as stated earlier we've been dating for a month and a half.

Can you succinctly summarize the text in 1-3 sentences?
<bot>: Gf says she loves me, I don't love her back yet. What do I do if she says it again?