Bay suffered the concussion after his head made contact with the left-field wall on what became an inside-the-park home run by Cincinnati's Jay Bruce on June 15.
"The first few days I kind of felt a little groggy, a little headache and stuff," Bay said. "But over the last probably two, three days, I feel astronomically better. I did all my tests, all that stuff, and am waiting to hear back (from the doctors). ... Hopefully in the next couple of days I can start up activity again and go through that progression and within a couple of weeks be fine. But I actually feel really good."
Bay noted he is not out of the woods until doctors clear him and he begins to attempt physical activity to see if symptoms return.
"The activity part of it, that's the ones that usually tell you where you're at," Bay said.
Still, he is confident this concussion is much less severe than the one he suffered two years ago at Dodger Stadium, which ended his season.
Bay played two additional games after that episode on July 23, 2010, then flew cross-country with his teammates.
"I can't rank it, but last time I ran into the wall and it didn't feel that bad," Bay said. "I played a couple of games, flew back -- did a lot of things that I didn't know any better, because I didn't feel that bad. That really put me behind, in talking to the doctors.
"The first week after any kind of head ordeal is important. And this time, someone drove me home. I kind of had a week at home of really relaxation, just kind of doing nothing, and really turned the corner after five, six, seven days or whatever. ... I know it took me a lot longer to get to this point two years ago than it did now, so I actually feel really good."
Concussions can have a cumulative effect if multiple are suffered. Bay said he has not been formally diagnosed with any beyond the two instances with the Mets, although he is sure he has experienced others that have remained under the radar.
"It's not ideal. That's for sure," Bay said. "I take a little solace in the fact that there hasn't been one or two big ones where you're completely knocked out. Those ones are real tough to come back from. But there is a concern, no question. I'm not going to say that there isn't. At the same time, it's something you try to forget about it, and you try to keep going.
"I think you can ask anybody in here. Especially in talking to the doctors, you can diagnose concussions with just a dive -- some guys slide and the impact of hitting the ground. There's a million different things now. Have I had more? I'm sure I have. I can't tell you. I'm sure everybody has. And that's the other scary part of it as well. But, like I said, what do you do?"
Bay has a habit of disregarding his body and crashing into walls. He also fractured a rib earlier this season on a diving catch attempt.
Can he tone down his aggressiveness ever so slightly to guard against another injury?
"My wife made that joke already: 'We've got walls in the house. Don't run into those,' " Bay said. "That's the one thing I can control. And, believe me, when I'm going back, that wall, I know it's close. If I was a foot away, I don't think I would have torpedoed into it. I know that they're there.
"I also feel like it's in the realm of effort that I can make a play. Unfortunately, doing that, I know there's an outside chance something like that is going to happen. ... I feel like you play the way you play. And if you don't, if you start playing a little more tentative, you're not being yourself. And all of sudden you're laying up on balls you can catch standing up. I can't answer that question yet, but I think that's just how things go."