Im not even certain that someone buying 0.00004 BTC at $10,000 is going to push the price up at all.
If someone is willing to pay 40 cents for 0.00004 BTC, and nobody is willing to sell it for less than that, then the price becomes $10,000 per BTC. In other words, it doesn't matter what amount is being traded, just the price it's being traded at.