I don’t know how to show affection to my gf.

My (18F) girlfriend (17F) and I have been dating for a few months now but before that we’ve been friends for years. Before we were dating we hooked up a few times and we both knew we liked each other so eventually we got together. For the first two months we were good, we were intimate and stuff but the past few months we’ve barely even kissed. I know that might sound weird but this is both of our first relationships so it’s all kinda new. I’ve realized now that everytime we did stuff it was her initiating it. I’m super shy and have a tough time expressing my emotions so I have no clue how to get that back. On top of that I know that she struggles with initiating things because she has past trauma from SA (she’s always needs constant confirmation that I’m okay) which super sweet just makes it difficult when neither of us can make a move. I know she’s waiting for me to make the first move but I’m always too scared to try and I have no idea how. But it feels like we’ve just returned to how things were when we were just friends only we have a different label. I feel so bad because I’ve never been a touchy person so she’s probably worried about overwhelming me.

I just feel like the longer we go without doing anything, the harder it is to start. Also it would seem weird if I had a complete switch in my behaviour and started being super affectionate? But i wish i was an affectionate person. How do i do that?