I hereby propose that the girl the OP likes is straight, but that the OP is the closeted gay.

Seriously dude, you got your hand on a boob, and then did NOTHING????
That is the biggest green-light on the planet.


Here's what you do:

1.) recreate the situation (lying on bed in room)

2.) get hand on left boob.

3.) instead of being a poon, engage the other boob, and go for the full on double handfull.

4.) proceed to have unprotected sexes.