We start the chapter off with yet another confrontation between Tom and Gatsby. The difference is Tom suddenly suspects that "Daisy comes over quite often - in the afternoons" and spends time with Gatsby. And Wilson has also discovered that Myrtle has a "life apart from him", but does not yet suspect Tom Buchanan. (Did you love the cost of filling the gas tank on Gatsby's car? $1.20!)
One of the interesting (but probably unintended) coincidences in this chapter is when Tom suggests stopping at a drugstore to get gas for Gatsby's car. "You can buy anything at a drug-store nowadays". Later, Tom reveals that while Gatsby claimed to have made his fortune from a string of drugstores, Gatsby and his business partners were really buying up small drugstores and using them as a front for selling ethanol - highly illegal in the Prohibition era. Ethanol (pure grain alcohol - aka "Everclear" or "Moonshine") may not have been used as fuel in the 20s, but it certainly is now!
It's pretty obvious that Daisy did not hit Myrtle on purpose. Myrtle was horribly upset, and ran into oncoming traffic. In the current day, had Daisy stopped and called 911 for Myrtle, she would probably not be cited. However, Daisy "floored it". That's "Felony Hit and Run." Not good.
With the realization of what she did, Daisy understands that Tom is far better able to shield her from the the consequences of her action that Gatsby is. It looks like Gatsby is about to get thrown under the bus.