your age permits some slight variations in the regularity of the cycle which is not actually a cause for alarm. Ensure that the blood coming out is not from the uterus
,menses. If its the case, it should be from the bladder or around there, suggesting most of the time a urinary infection.
However, observe well again for a few days, and if nothing comes out persistent blood comes from the bladder, consult your physician for a proper evaluation and management. as of now, drink a lot of water and be calm.
Do not hesitate seeing your primary care
physician in case it worsens,