Dripping tap after trying to clear airlock?

I wasn't able to get hot water from any of my taps so I used advice from this website to cover the mixer tap and turn on both hot and cold taps to clear the airlock. That seems to have worked and now all of the hot water taps are back to normal. However, since then the tap in the bathroom has been hissing intermittently and is dripping quite a lot. What might the problem be now?