Baggage and new relationship

I'm having a hard time not having poor expectations for my new relationship. My last one wasn't the greatest and though not all guys are the same. Every time the new guy does something well or unlike my old relationship it shows I'm not used to it. Which isn't good. I don't want to bring old baggage it's just every time something goes well it throws me for a loop and i think that reaction can be off putting to him. How do i not have that surprised reaction to the new man.