Was I too permissive?

My teen daughter lives with her father (he could afford a divorce attorney; I could not in the end, so I got screwed).I just found out that she was suspended from school after being caught having sex with her boyfriend in her car, in the school parking lot. I promise you, I am not a fan of this, but her dad is SO controlling that I put chastising her off. I also had a problem as a teen; I was so (rightly) terrified that my mom would find out what I was up to that I ended up not being completely safe about it because I couldn't go to my mom for help in getting birth control. I ended up pregnant at 19, partially because of that.She's a lot like me. If you tell her not to do something, she'll just move it underground, and you very well might never find out what she's doing, so I went gentle on this.I asked her if she was being safe, and she swore she was. I told her that no matter what, if she didn't feel like she could talk to her dad about all of this, that she could always come to me and I'd help her. We'd work out whatever was needed. Thankfully, she said her stepmom was going to put her on the pill.I also asked if her boyfriend was coercing or forcing her in any way, and she swore it was 110% consensual. I did tell her, just for future reference, how to take a guy down if she needed to.The other problem is that her dad has been keeping her phone away from her for months now because of something she'd done before. I completely disagree with this, especially with what's going on at the moment. I just worry that she could end up in a dangerous situation and unable to reach either of us.God, I wish there was a manual for all this!Thoughts? via /r/Parenting http://bit.ly/2Jftqs9