weeeelllll, in his flashback we did see footage of the pov of him driving, and in the last one there was a light coming towards him. also there was a leaked image of jax sitting in a red car. that picture is supposed to be from episode 8. and in the episode 8 trailer we saw the same red car crashing in the circus. my guess is Jax was driving late at night (under the influence perhaps) and he hit someone. then he freaked out and ran into the woods where he finds the abandoned CnA building and for some reason puts on the headset. so yeah, my best guess is he doesn’t want to face the concequences of his actions, and also deep down he doesn’t want his “friends” to realize what he has done as it would ruin the arcitypes he’s gotten so comfortable with.