Tottenham, who are mounting another serious title challenge this season, almost left the Hawthorns with no points after falling behind to a Nacer Chadli strike in the 82nd minute.
However, Alli was able to find an equaliser in the 89th minute and Spurs left with a share of the spoils, although the dropped points have seen the club drop to third in the Premier League table.
The visitors dominated for large periods of the match and were only denied the win because of a fantastic performance from Baggies goalkeeper Ben Foster, who made a string of top saves.
Next up for Mauricio Pochettino's men is an away trip to Leverkusen in the Champions League on Tuesday and Alli wants to get straight back into the thick of it to put things right.
"I can't wait, we can get back out there and get some minutes and get the win," the England international told the club's official site. "We have to keep going and pick ourselves up but there are a lot of positives. In the next game we have to make sure we put them (chances) away."