Proactive made my skin really dry and flaky?

i have used proactive for about 2 years now, same products the renewing cleanser revitalising toner and repairing lotion 2 times a day using the oil free moisture every morning, and the refining mask once or twice every fortnight, and the makeup removing cloths occationanly. anyway all of a sudden my skin got really dry and flaky all over my face, so i havnt used it for about two weeks, but vie been braking out a lot since i stopped using it. Whats happened? is it because i need new products i was thinking it was because it takes me awhile to use the bottle (maybe 2 1/2 months?) i got new pack in the mail, should i open the new pack and not use the old pack? or is it because i put to much on or what?