We don't know. That's part of what's made COVID so difficult to manage - it's a new virus being fought with relatively new vaccine technology. Most of us are u

We don't know. That's part of what's made COVID so difficult to manage - it's a new virus being fought with relatively new vaccine technology. Most of us are used to doctors giving us advice that's pretty stable and based on decades of research. But, in this case, most doctors don't have that much more information than what's being reported in the media (but they have a clinical background that helps interpret the results generally better than the public). Further, your doctor is going through the same emotional hurdles you're going through (e.g., wanting to get back to normal asap). Jab count probably does matter, but I'm not sure anybody definitely knows how this plays out with these vaccines specifically (and, nobody can predict how the vaccines will respond to yet-unknown variants). In general, multiple exposures can impact antibody durability, the amount and types of antibodies you produce and even cause changes to the antigens your body will respond to. These aren't unique mRNA issues -- immunity issues exist with all types of vaccines. So, it's great you're getting your third shot. It's probably safe to assume there'll be more shots in the future; what/when those future shots are isn't known... any specifics you get from anybody right now is just their guess.