Curtis Tilt produced a remarkable overhead kick in the 92nd-minute to make it 2-2, after Marc Bola had pulled a goal back just seven minutes earlier.
Plymouth had appeared to be cruising to a comfortable away when thanks to goals in either half from Freddie Ladapo and Ryan Edwards, but they were punished late on.
McPhillips admitted his side's display was well under-par but was delighted with how they fought until the end.
“They have got some spirit about them," the Pool boss said.
“We haven’t played great, have we? They played our pitch better than us.
“I think in the last two home games before this, that we also drew, we were the better team in both.
“But if I’m being honest I couldn’t see this performance coming today because we haven’t played as well as we can.
“If you watched us last week at Bradford you’d think ‘wow’ but we obviously got no where near that standard today.
“Fair play to Plymouth, they’ve got good players but we dug deep and showed some bottle.
“It’s football though, isn’t it? It’s 95 or 96 minutes and these lads do go until the end, so you have to give them great credit.
“I thought the crowd helped us again, they were immense and we’re so desperate to give them a win here at Bloomfield.
“You get the one goal back and you start believing, then Tiltinho does his overhead kick.
“To be fair to Tilty, he has done that in training before so it wasn’t a total shock. He’s come up trumps and he’s got a habit of scoring late goals.
“But as a group we kept going despite not playing well. That’s football, there’s no guarantees and you can’t promise anyone you’re going to win a game.
“But we can promise them we’ll have a go until the end and they did.”