According to USCF rule 14E2, if your opponent has only a king and knight (and no forced mate) and you run out of time, the game is drawn. According to FIDE rules, the game is not drawn if there is any legal sequence of moves leading to mate. Chess.com appears to use something similar to the USCF rules for this situation; it says "... note that in cases where the opponent has insufficient material to mate (lone King, King + Knight, King + Bishop, King + 2 Knights) a draw will be automatically declared where there is a time-out." So even if the game doesn't immediately end and you've only got 5 seconds left, you don't have to panic.
Also, if a checkmate is possible, would it have to be as a result of a
blunder or would it be able to be forced?
In the position you give as an example, even a single "blunder" isn't sufficient to lose. Your opponent can't even force your king to move more than one square from where it's sitting, let alone force it into the corner; and even if you did move it to the corner, there's no way to force your knight to go alongside it when it literally has the entire rest of the board to use. A checkmate would probably be the result only if someone was trying to lose, although it could perhaps also happen if there was an extremely ill-advised attempt at inducing a stalemate.
But it is possible in other positions that the knight vs knight situation happens in exactly the right spot for a forced mate in one (which is probably why chess.com does not simply declare a draw when you reach knight vs knight.) Here's an example where Black is forced to take the White queen with his knight, setting up a knight vs knight checkmate.
[White "NN"]
[Black "NN"]
[FEN "6qk/8/5nKN/8/2Q5/8/8/8 w - - 0 1"]
[SetUp "1"]
[CurrentPosition "6nk/5N2/6K1/8/8/8/8/8 b - - 1 2"]
1.Qxg8+ Nxg8 2.Nf7#
Interestingly, there is no point where Black could abuse the time-out draw rule and intentionally let his clock expire for a draw; before he plays Nxg8, White has sufficient material. So stalling can't save him in this position.