Recently, I had a clog in my bathroom sink that I wanted to attempt to fix myself. Believing the clog to be in the P-trap, I bought a pipe wrench, removed the trap, cleaned it out, and attempted to fit it back onto the sink (side note: the clog was actually at the top of the drain, which I later discovered; who knew?). However, when I attempted to reattach it, the pipe that drops down from the base of the sink came detached — it appears that it was only held on by some kind of seal between it and a rubber washer. Now, when I run water, it leaks out of the base of the sink (and also the top end of the P-trap, but I may not have tightened that enough).
How should I go about reattaching it? Is it as simple as getting some kind of putty to fix the seal, or am I maybe not aligning the P-trap correctly?
Edit: I thought an illustration of the problem might be helpful: https://vimeo.com/68243871