Gaining confidence with relationships!

Hi guys so I have a question my boyfriend and I have been a relationship for almost 2 years I am 15 and he has done a lot of things in our Relationship and I feel that I haven’t done anything because I’m too much of a chicken like I want to do things but I’m scared like I freaked myself out over it because I’m not confident and it akind of disappoints him and it makes me sad to see him disappointed and it makes me disappointed at the same time because I know I want to do things but it’s hard because I overthink them any advice or suggestions?