The visitors had already drawn level through a controversial Glenn Murray spot-kick in the 82nd minute, but Thomas went down in the box in stoppage time in the hope of seeing referee Mike Dean point to the spot for a second time.
Instead, Thomas was booked for simulation, and Palace manager Pulis stressed there was no place for behaviour of that kind in his team.
"I've spoken to Jerome," said the Welshman. "I think JT has fallen over any touch and he'll get fined for that.
"I think (Marouane) Chamakh did it as well in the first half and he'll get fined as well.
"Over the past couple of years, the country has cleared those situations up much better.
"(Thomas) has been in and seen the referee and apologised to the referee which is good, but I just don't have it at football clubs I manage."
Jonathan de Guzman broke the deadlock for Swansea in the 25th minute, before Chico Flores was judged to have felled Murray in the penalty area late on.
The initial contact appeared to be made outside the area, but Dean produced a red card for the Spaniard before Murray powered home the equaliser from the spot.
"I think the first touch is outside," added Pulis when questioned about the decision. "But if you have a look I think he does touch him a second time in the box."
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