It sounds like you're right on target with your increases. You may be counting the number of rounds you've done (20 so far) and not the number of repeats of the 2 round pattern (10 repeats so far). The 10 repeats have given you 80sts increased (64+80=144sts). You have 18 more repeats of the 2 row pattern or 36 more rounds to go for 288sts. So just keep going, you're doing fine and the pattern numbers look right.
