"Then why is the price going down, now under 17? "
Institutional trades only accounted for 41% of trades today. There were about 3.5 million retail trades (individual investors) who were probably sellers.
Also the price of a stock is determined by the amount a buyer is willing to pay. When sellers are willing to accept a lower price for their shares and corresponding buyers are willing to buy low then the share price moves lower. For every seller there is a buyer etc. etc.