Besides Fold Pre-Flop possibility, is this how it should look like?

Villain has $80 and I have him covered. No reads.

I have [6d] OTB and raise to $2.50 after Villain limps in HJ..He calls..

Flop [5d][6s] ($5.50) .. He checks, I bet $5.50.. he calls.. I am nervous..

Turn ($15.95) .. He checks.. I check.. He might have a draw or something like KJ here because I think he is "capable" of calling PFR with that.. He might also have something like 99 , TT or Flush Draw..

River ($15.95) .. He checks.. I bet $15.50 ... looks fine?

Looks fine.

I bet the turn, this is the perfect spot to second barrel semi-bluff.

ok.. i get that.. cause of the nut flush draw that i get on turn.. what do I do if I completely miss the river and still have only pair of 6 ?