You're flying in F from DFW connecting to Jetstar! You'll regret it, really, Jetstar, it's worse than Spirit airlines. And pray there's no irrops, you could be stranded for days.

Singapore's a very efficient airport and you'll probably have time to collect your bags and check in again but your best plan is to miss the Jetstar flight and buy another ticket on SQ (MI) or Garuda.