7 hi/lo @Foxwoods...did i misplay this?

[edfreeze]

Playing $2-10 7 hi-lo with a half kill @ Foxwoods on Thurs. I'm dealt 3 [img]/forums/images/icons/diamond.gif[/img] 4 [img]/forums/images/icons/diamond.gif[/img] 6 [img]/forums/images/icons/diamond.gif[/img] Brought in for $2, I raise $2, five callers. The 5 [img]/forums/images/icons/diamond.gif[/img] is dead. Fourth street brings me 7 [img]/forums/images/icons/diamond.gif[/img] I bet $5 since the other players looking low have caught bad or worse than me, and I figure I'll be put on a low and called by high hands that I can sweep when I make my flush. Called by three other players. Now I catch bad. I bet $10, wanting to push all other low draws out of the pot and hell maybe take it right there, I had been called all along and no one was showing much enthusiasm for their hands. BUT the guy across the table from me just caught a K [img]/forums/images/icons/spade.gif[/img] for his third up spade, two of 'em above 8. He raises me $15. I'm the only caller. Long story short, I call him down to the river, don't make my low or flush, he's got his flush.
Now I don't know he's got a flush of course, he could have made kings up or even a pair of Ks and put me on a busted low (partially right) With a lot of dead money in the pot, was I right to invest another $30 in the pot on a low draw (2 cards to come for a low card for 1/2 the pot - my cards were pretty live) or a sweep (which of course would have required me pulling the A [img]/forums/images/icons/diamond.gif[/img] as he already had his king-high)?
Would like some input as I brooded about this hand for a little while...

ALSO: I also don't seem to get away from big pairs quickly enough in 7 hi/lo. I'll start with As or Ks of Qs and bet strong, get called by people I put on a low, and push and push til the river, waiting to pair up or thinking, "I know I'm leading at this point, even if I don't hit my second pair. These guys must be looking low" Too often of course I don't hit it and lose to low straights or a guy going low who made 5s up. Obviously if my cards are real dead or someone elses hand threatens or someone bets hard with an overcard, I get out. Any tips on this?

Thanks in advance to any responders. Love the forums.

edfreeze