Flopped Q's, tough river decision

[seabass74]

I 3-bet in late position after with QQ after 1 early limper. The SB calls and the BB folds. 3 to flop of AQ4r. Check, check, I bet 15, SB calls, 1 fold. HU to the turn of 7 completing the rainbow. Check call. River is a 6, SB looks at board, looks at cards and shakes his head like he missed. I bet, he checkraises,... I felt like all three options were viable... btw he was a huge fish, very loose and I hadn't seen him raise yet although this was only like the 3rd orbit.

If it helps any he only had enough chips for 1-2 more BB's after the check raise.

It's your move... thanks for any replies.