Never check more than one street to slowplay unless you have like quads or some hand that literally can't be beat is my opinion. I mean, you have to build a pot either way. I'd have bet just enough on the turn to give all possible draws a bad price, and if they call then it's their idiotic luck, but yeah a turn bet was probably correct as it forces draws out and starts to build a pot. Hope they have QJ and will pay off a little or something. Hard spot and tough break tho.