Gareth Bale struck in the final minutes to earn a 3-2 win for the visitors.
"It's sickening to lose when you've played so well and you have a valuable point taken away at the last minute," Jarvis told whufc.com. "Bale has turned and stuck one right in the top corner. It's hard to stop that, but we played well and that's why it's hard to take. But we've got to look at the positives that we did play really well, created some great chances and should have got a result."