Caffeine is quite a potent central nervous system stimulant in high quantities and is certainly capable of making you hyper as well as having numerous other effects. Is that in contradiction to the effect you desire from the Prozac?
Yes I would say it probably is to blame. Caffine is NEVER good in large amounts- ever. Especially when you are on these touchy meds. Try cutting your caffine intake in half- or at least cut down a third of it and see if your results change. My guess is they will! Good luck hun.