I took plan b a week ago and i am still feeling very fatigued how much longer should this last? i also have brown spotting for the last 3 days.

Plan B: Plan B is a progestin and is expected to disrupt ur menstrual cycle.It is however out of ur system by now and, although progesterone can make u sleepy,it is unlikely to be the cause of fatigue at this point.Remember that Plan B is only 95% effective if taken within 24 hours after unprotected intercourse so u might want to do a pregnancy test next week and repeat it 3-5 days later if it is negative