600/1200 with 200 ante. (Level 10-ish, Day 1 ends at level 15)

My Stack: 120K. Unknown young gun.

BB Stack: 150K. Old, stubborn aggro reg.

Preflop: I had 8c8h from +2 and opens to 2600, get called by D, SB, and BB.

Flop: 4s 7d 8s.

Checked around to me, I bet 4,500 and get called by BB. He called rather quickly.

Turn: Jc

BB checks and as he quickly taps he said "checks to you" almost friendly, and I bet 10,600 and get called.

River: 5d.

BB shoves all-in. He said "ALL-IN!" in an in-your-face manner, very hostile this time. I confirmed with dealer that he did have me covered. What do I do? If he doesn't have six how could this make sense? I was so hoping to trap and punish him.

Annoyed, I folded (presumably correctly), thinking this calling station just called off with As6s and I should've shoved the turn, or better yet put a 7s in there for max enjoyment.

0. Is there a chance that the old guy is bluffing me here? What really his range here? He is relatively tight from EP-MP but quite a wide defend range plus got really solid odds to call with any two. QQ+ definitely would have heard from him tho.

1. Did I misplay this hand?

2. What bet sizing would've been better?