Sb - snodderly has good advice and I would like to offer another perspective. To wait and walk slowly may work - you know what your daughter is like much more than we do. And my own kids are too young, but there are important children in my life that are around the same age.
You should confront your daughter today or tomorrow, as soon as possible. If she almost had sex last weekend, there's bound to be more experimentation (without going into details making out for most teenagers includes oral/anal "not"-sex.)
I personally think your daughter may yell and scream and go ballistic, but it may be a HUGE relief to her as well if your punish her for the next month. Throw her a rope, let her know you care
Today is Wednesday so the plans in your daughters world are being made right now. No time like the present to give the gift of love in the form of a grounding.
I know this is hard on your and you are in my thoughts. Plus, in a way standing up for your daughter against peer pressure (pot/sex) might give you the strength you need in this tough time.
. (note / I'm posting under the assumption that you are not ok with her actions, some parents are and have no problems with drugs and sex)
