NL200 in a weird situation when I hit trips on the turn

[DHamilton97]

Party Poker No-Limit Hold'em, $ Hero (6 max, 6 handed) pokerhand.org hand converter

UTG ($100.40)
MP ($284.65)
CO ($93.90)
Button ($172.40)
SB ($211.60)
Hero ($298.35)

Preflop: Hero is BB with 6[img]/images/graemlins/diamond.gif[/img], 6[img]/images/graemlins/spade.gif[/img]. SB posts a blind of $1.
UTG calls $2, <font color="#CC3333">MP raises to $8</font>, <font color="#666666">3 folds</font>, Hero calls $6, UTG calls $6.

Flop: ($25) 5[img]/images/graemlins/diamond.gif[/img], 4[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG checks, MP checks.

Turn: ($25) 6[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets $11</font>, UTG folds, <font color="#CC3333">MP raises to $40</font>.

Final Pot: $76

I wasn't sure if he was slowplaying aces or what. I felt it was very possible. He couldn't have a lower end of a straight as he wasn't THAT loose. He was somewhat loose aggressive but nowhere near a maniac at all so AK and many hands could be possible. What to do?