Someone who is bipolar would not be affected as described. Bipolar is a disease where a person cycles between emotional highs and lows, but it very rarely causes memory loss or psychosis as described. This would only occur when a person has other underlying conditions such as schizophrenia. It is possible that Carrie was given other drugs that may have impacted her. The only time Carrie exhibited psychotic behavior is when someone tricked her into taking a drug more powerful than LSD.
When Carrie meets her Afghan contact to drive her to Roshan's home, the Afghan indicates that he has a new truck with a capacity of 10,000 gallons. The truck is too small to hold 10,000 gallons which would be about 80,000 pounds, and around 40 feet in length.
There is no need for President Keane to re-take her Oath of Office. Under the 25th Amendment all she needs to do is transmit notice to the leaders of each house of Congress to immediately resume her powers.
Staff Sergeant John Durkin mentions to Max Piotrowski during a field operation that the U.S. Army unit protecting him were present during the attack on the U.S. Embassy in Islamabad. However, prior to the attack, then CIA Director Andrew Lockhart mentioned that U.S. Marines were present at the Embassy, not U.S. Army personnel.