When Starr and Benson are in the diner, Starr has steak and scrambled eggs on her plate. The camera then cuts to Benson briefly, then when it cuts back to Starr, there are two pieces of toast on her plate that weren't there before.
When Detective Elliott Stabler (Christopher Meloni) is knocked to the ground by the force of the dynamite explosion, the impact as he hits the ground wounds the left side of his head and he's shown having bled severely. The next time we see him - too soon for the wound to have healed naturally - his head looks normal and there's no sign of the injury.
During the final stand off, Olivia is very concerned about the bomb. She was one of the people that brought one of the ingredients. Why would she bring an actual bomb component? They could have filled a fertilizer bag with kitty litter or something similar but inert and the bomb would never work.