Hi Lein!
Romanized:
Anata ga boku wo ai shite imasu.
Yes indeed, it does mean You love me! (?) ---
And the way of saying it in Japanese is also kind of strange, because the "me" is a male(there is a special form for "me" that men/boys use in Japanese, which is used here), and usually a male would not use the word that is used here for "you" ("anata" )to his girlfriend...?
It sounds like he's talking to an older woman he respects (for example his teacher?), or someone he doesn't know very well...
Also, the politeness level used here is usually for strangers, not for people who love each other (especially when this politeness level is used by males...?) ---
But anyway, I guess it's validate-able!