Yes, it is entirely safe to stop taking the prednisolone after just one 5mg dose. Stopping after a single dose will not cause any withdrawal symptoms or harm your body. Since these two medications are designed to work together in a coordinated cycle, waiting and restarting the treatment next month when you have both medications ready is a practical approach. Please consult your prescribing doctor to inform them of this minor delay and to ensure you have all your prescriptions filled and ready well before your next period begins.