how to say no to fwb situation?

so me and this guy are talking about possibly being fwb, but I decided it’s not for me and I think I would just end up feeling bad about myself AND i’d catch feelings. i told him i would think about it so he’s waiting for an answer. should i say something like:

“so I thought about it and I don’t think we should do it. I’d probably catch feelings and that’s not fair to you. sorry :(“

this is how I feel and I know he doesn’t want anything serious so it wouldn’t be fair to him or myself. is this okay? or is there a better way I can say it? if so, write it below. thanks :)

I almost feel guilty for saying no like I led him on or something but I know it’s just not a good idea for me.