Re: Why does price fall when I buy and it rises after I sell?
I'm not sure I quite understand this. It has happened every single time I bought a coin. Whether it's BTC, VTC, XPY, BC, DRK or even LTC. It doesn't matter what I buy it shits itself as soon as my buy order goes through. As soon as I get tired and sell it starts going up. 
Because you want to profit too much
You say you buy coins, the profitable way is, you don't buy coins you get your buy order filled so in the end they sell to you at a much lower price,
You don't sell your coins, you just wait, 2 months, 5 months, then finally you dump them to the highest bidder at a spike at any price above the original price you paid to get them.
That's how you profit,