Continuity mistake: When Margaret is first stabbed in the chest with a kitchen utensil, in one shot there's no blood in the wound, but in the very next shot there is.
Continuity mistake: In the scene in the beginning of the movie when Carrie's mother puts her in her "praying room" the room is pitch black. When it cuts to an overhead shot of Carrie in the room, the room is lit either by a window or something else. This is before she lights a candle.
Continuity mistake: Before Carrie goes to the prom while her mom is lying on the bed, her head changes position between shots.
Answer: Since blood was dumped on him too she must have realized that he wasn't a part of it, so yes, she cared for him. In the book when Carrie touches Sue, they link minds and Carrie sees that Sue felt bad about teasing her and was trying to do something nice to atone, and had nothing to do with Chris' nasty prank. So yes it's safe to say she grieved for Tommy and forgave Sue.
Grumpy Scot