Yep, just keep offering. Hop in the bath together, and see if that helps her to suck. She's probably feeling pretty icky and hot, so feeding in the relative cool of the bath may be more enticing. It's important to get some extra feeds into her if you're worried about dehydration. If you're still concerned call the ABA helpline 1800 MUM2MUM (drop the last digit for VOIP phones).