Why can’t I just be happy

I have found the love of my life. We have been dating for a few months but everything is perfect. I don’t know how to explain it other than when you know, you know. He is the one and the happiness I feel is insane. I’ve never felt like this about someone and he reciprocates the same level of love it’s just amazing. I’ve never been treated right and now I’m getting flowers and reassurance. It’s perfect. Before this relationship I went through many toxic hurtful ones. I’m scared that i’m too damaged to enjoy what is obviously right for me. I don’t know how to cope with the feeling that I don’t deserve this treatment. I just want to be happy and whole but I have a constant nagging voice questioning everything. Has anyone else experienced this? Is there anyway to fix it?