If you buy a bitcoin in the price of 9000$, yes it may drop, but we have clearly seen that this is what it does. It goes up and down. If you have 1 million dollars and buy 100BTC (900.000$) then the only thing you have to do is wait. Because someday it will pass that number and you will have profit. Am I wrong?
If I have that amount of money I would never spend it in just 1 buy order. I would divide my capital into 2-3 so even if the price goes down I can still buy at that price. Don't be so confident that it will surely go up because you don't know when would that happen. You bought bitcoin to earn profit not to become a hodler for a long time.