Continuity mistake: When Travis goes to visit Dr. Rand to tell her what happened, she sticks a shotgun through the opening in the door to drive him off. Once he explains who he is, we hear the door unlock. In the next shot, when Travis walks in, Dr. Rand is instantly on the other side of the huge penthouse.
Plot hole: Travis does the last time jump to change the events of a previous time jump. As all the jumps were to the exact same time to kill the same dinosaur, the travelers of the second jump must have found there the travelers of the first one. The travelers of the third jump must have found the travelers of the second and the first, and so on.