This low dip also make me think buying more for short term as we may see another rise upto 500 and than a little drop like this, this is how natural trading curve works. Hope there will be no manipulation in the market.

I am holding all my coin which i bought when price was 390 around so still i am in profit in this dip.
No manipulation? since in 2016 market on condition manipulation by big trader see the price stable around $400 for a long time. it's so weird i expect we get new investor to push the price up.
My guess is the "price" of bitcoin is at any time about 90% speculation. And we have very sophisticated manipulators moving it around. It is neither good nor bad just a fact. the manipulators ability to influence the market at any time is greater than the possible market moving items eg halving, segwit etc.
So its real wild west territory - you can make it big or lose big depending on how much luck your timing is to when the manipulation happens.