When Dr. Tsang fixes Clarke's arm she is wearing a dress, but when Clarke hides in the cage with Anya and Dr. Twang walks by she is wearing a shirt and pants.
Clarke's cut on her arm does not match up to the previous episode. In The 48 (2014) she cut her right arm in this episode she has the cut on her left arm.
The ar15/m16 platform rifles used by the kids should not "click" more than once when a bullet fails to fire. Often the kids are seen pulling the trigger multiple times attempting to fire a "dud bullet." Each time the trigger is pulled by one of the kids a click is heard. This click is the hammer dropping and striking the firing pin; however if the bullet fails to fire, when the hammer drops the only way for the hammer to fall again and create an audible "click," the charging handle must be pulled back cocking the gun.
The outside shot of what is supposed to be Mount Weather is shown with several satellite dishes still intact on it. These probably would not have survived a nuclear blast that occurred near Washington D.C. The shot also prominently features a lake and a dam. The real Mount Weather is isolated from water, the closest large body of water being the Shenandoah River. The President tells Clarke that they have access to Phillpot Dam, which is on the southern end of Virginia while Mount Weather is on the northern tip of the state.
The "mountain men" living in Mount Weather use blood transfusions from multiple people without any apparent regards to blood type. Blood is not a universal type; if people received transfusions of the wrong blood type, their body's immune system would begin to attack the foreign blood causing massive clotting, organ failure, and death.
Octavia is a girl who lived her whole life in a very limited space and it's seen easily restricted by boys of her age. She is not a girl with physical strength, but she somehow manage to left "unconcious" a strong adult man by just a simple hit with a small rock, and keep him restricted from movement.