Too shy in the bedroom

Anyone else has the problem of being shy in the bedroom? My boyfriend wants me to do more in the bedroom, sexy stuff. I'm just so insecure about my body. He wants me to put sexy lingerie on or walk around naked or even climb on him and say dirty things. Even if I want him I'm too shy to make the first move. we can only do it in the dark and I hate when he watches me undress or anything. After having my son my body jst isnt as tight as it used to be. wanna get sexier? What u girls had in mind? And do any of you relate?