Of course, for every trade there is a buy and a sell. But that's not what's being monitored. A trade is considered one or the other by whether it goes off at the bid (a sell) or the ask (a buy). Consider it a tracking mechanism that determines overall market sentiment.
Because someone is selling directly into the bid at 14 of course there’s someone waiting to buy but level 2 doesn’t show all the shares like level 3 but the initial trade is someone initiating a sell into the 14