Weird game

I ended up playing one late-night game last night. I was Terran on Metalopolis. My opponent was Zerg. He starts messaging at the beginning of the game, saying that he is really bad at Zerg. I chat a bit, but I play normally. When I scout him, I notice he fast expanded, so I start building an army. I drop on him, but it's repelled. I don't lose any of my medivacs, though, because he has no anti-air units. I lift off my starport and build a tech lab. I build a banshee and harass with it. Surprisingly, it gets 7 kills, without really managing it. I didn't really pump out any banshees, but I keep going. Right when I start to push out, he attacks. He swarms around my tanks and my marine-marauder army and kills it with zerglings and roaches. I think the game's going to end soon. He pushes up my ramp, but I manage to hold it off, slowly killing off some of his units. He makes it into my base, but the units that keep coming out managed to finish off the rest of his attacking force. I realize that my siege tanks didn't have siege mode researched, and that I didn't upgrade my units at all.

Then... Nothing. I message him, wondering why he's not attacking. Meanwhile, I'm frantically trying to build up my army again. I build another command center (behinds the one at my natural) to try and get back in the game. Finally, when he does attack, it's with a massive zergling army and a huge amount of... queens? They funnel into my base, and they get worked because they are so slow. While the zerglings are dealt with by my tanks, the queens start melting under the tank fire while attacking the marines and marauders. His army evaporates. He messages, "I can't take this seriously. This just shows how easy Terran is." Then he leaves.

I win my 42nd game, but I'm at a loss why. Maybe he really didn't know how to play Zerg. I checked the replay, and I guess he was sort of floundering. Weird.