i bought $5k worth of alibaba stock when it was trading over $100. I lost about $1000. i am not sure what to do now. some analysts feel its gonna sink lower. is it a good idea to hold what i have now or sell and then buy back when it goes lower?
Presumably you had some idea why you bought it at $100? Does that thesis still stand? Has anything fundamentally changed in the investment case? If you think not, then keep it. If it was a good buy at $100 then it's even better value at $84, and you can rue your impatience making you overpay, but otherwise feel happy in your decision. Otherwise cut your losses.
AFAIK the "lock-up" period of BABA shares has just been and gone, a dip was expected leading up-to this point - however I believe the BABA employees with options didn't dump as many shares as were expected.
If you're into this share for the long haul you should be just fine.
Think of it this way, in 10 years the shares might very well be pushing 1000 USD each.