When an INTERRUPT (any interrupt) occurs, your program will jump to the part of your program designated as your Interrupt Service Routine. It is the job of your ISR to determine what caused the Interrupt and then act on it. You can only have ONE ISR jump point, but once you're inside your ISR, then you can check what caused the Interrupt and act on it. Interrupts have rules (like not allowing interrupts to interrupt interrupts I know it looks corny but it is gramatically correct!, and resetting Interrupt Flags), so it's better to read up on them before figuring how you're going to plan your code.