The safety, who is playing on the team's franchise tag this season, has missed the start of the 2013 campaign with a foot injury.
The 27-year-old told reporters: "Yeah, definitely. Yeah, I do feel like I'm back as far as just my body-wise. Now the rest is just mental, getting out there.
"A lot of excitement. This is what I've always wanted to do anyways from day one. Now we're here and I finally get to go play, so I'm excited. My first time being out there, just going to give it all I've got.
"I understand the position I'm in due to my injury that I have a lot to catch up. Just going to give effort wherever I can help the team is where I'm going to go."
The Bills play the Cincinnati Bengals on Sunday.