Is follicle size 13.5 on day 13 normal..?! will i ovulate this time

Small: The follicle usually reaches 18 to 20 mm when it is ready to ovulate. In the days preceding ovulation, follicles usually grow approximately 1 mm per day. Based on your number, i would guess you will be ovulating in 5 to 6 days, but this is just a guess, and it may be that you won't ovulate at all this cycle. Unfortunately it's hard to tell in advance what will happen. Would luck!