I feel bad after setting boundaries

It’s been a year and a half since I ended my toxic marriage with a person I was with for 7 years. I learned a lot from it and practice self love always now. I know what I want and the type of man I want moving forward. I’m not willing to settle anymore.

I’ve been talking to a guy for 3 months and things seem different with him. At first I was positive he’s a player so I didn’t take him seriously. But his actions have changed and I’m getting the feeling he sees me as someone serious also. He made a remark the other day about how no girl has ever left him and he’s used to getting multiple chances. I told him it wasn’t going to be like that with me because I’m not playing games and he has one chance. Then I IMMEDIATELY felt bad after saying it. This has always been my problem but it has made people step all over me in the past because I never used to set boundaries and I still struggle with it now. Was it a good thing to let him know that? Or should I feel bad like I was too intimidating or something? He’s still talking to me but I hope I didn’t change anything.