Factual error: Tru arrives "more than three hours late" for the MCAT and then begins the test. Firstly, it would be pointless for her to even bother going at that time, since she'd have already missed the entire Verbal Reasoning section and possibly the Physical Sciences as well (depending on how much more than three hours she was late). Secondly, that's really a moot point since late arrivals to MCAT testing centers are not permitted to take the test.
Revealing mistake: It was raining in Vancouver the day the outdoor scenes were filmed for this episode, so the actors were filmed under large tarps. When Tru and Paige walk together in the park, rain can occasionally be seen in the foreground and background, but not over the characters themselves. The ground is also wet everywhere throughout the episode.
Plot hole: There's too much bruising on Paige's arm in the original timeline, given that she only had one injection given to her by a med student (on the day of her death). She doesn't appear to have had any previous injections when Tru looks at her arm in the second timeline
Plot hole: The first time the day happens, Paige is quickly identified as the victim of a drug overdose. However, we find out later that she actually died by violent strangulation. Yet the only sign of trauma on the corpse was minor hemorrhaging in her eye. There should have been obvious signs of the confrontation, starting with huge bruises on her neck.
Factual error: This episode misrepresents the scheduling and format of the MCAT. The exam is given in four sections, with an hour lunch break between the second and third. The morning session lasts three hours and fifteen minutes, the afternoon two hours and fifty minutes. If Tru was "more than three hours late" (and, presumably, less than four hours late) when she arrived after 2:30pm, then it presents two problems. Firstly, the session should be in the midst of its lunch break. Secondly, the test started much later in the day than the real MCAT does.
Plot hole: Why hasn't Tru met Luc? He came to the morgue very late the first time the night happened in the previous episode, after Marco scared Tru. Even though Tru seemed to stay at the bachelor party very late the second time the day played through, she had gotten into work by the time Marco tried to scare her again, so she should have still been there when Luc came in.