Role play??

I really want to role play with my husband of 2 years but I'm just so damn goofy! I literally laugh at everything and I don't wanna ruin our first sober role play session by being silly and not being able to hold my playful role! Don't get me wrong, I'm as freaky as they come but when it comes to dressing up I feel so silly but it's something that he's been dying to try! We were successful ONCE but I was very tipsy and didn't give a damn. I'm pregnant now and obviously can't get tipsy. Any advice??