Uh... shoot. (Deepstack 10+1)

I've been playing very aggressive, opening lots of hands from different positions. Also firing lots of c-bets. Just last hand I raised and took down the blinds. (Villain was BB.) He's been getting tricky with both me and the other aggressive player at the table, but I felt he was playing back at me with air. When the third heart came on the river I was very close to checking behind, but thought I would get called by weaker hands due to my image, or just the nature of the board and my betting pattern. I really didn't expect to get check/raised two straight streets. I have to call/push here right? If I fold I still have 3455 with 25/50 blinds.

PokerStars No-Limit Hold'em Tourney, Big Blind is t50 (9 handed) converter

MP1 (t6810)
MP2 (t6295)
MP3 (t9040)
CO (t8470)
Button (t11880)
SB (t6805)
BB (t3695)
Hero (t7655)
UTG+1 (t3110)

Preflop: Hero is UTG with J[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/heart.gif[/img].
<font color="#CC3333">Hero raises to t200</font>, <font color="#666666">6 folds</font>, SB calls t175, <font color="#666666">1 fold</font>.

Flop: (t450) 4[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/diamond.gif[/img], 9[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, <font color="#CC3333">Hero bets t400</font>, SB calls t400.

Turn: (t1250) 8[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, <font color="#CC3333">Hero bets t800</font>, <font color="#CC3333">SB raises to t1600</font>, Hero calls t800.

River: (t4450) 6[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, <font color="#CC3333">Hero bets t2000</font>, <font color="#CC3333">SB raises to t4000</font>,???