Hi everyone. Ive been tracking my cycle this month and its CD 15 today and ive seen a lovely smiley face on my Clearblue OPK. I know they say you have 24-36 hours to have intercourse after seeing the smiley face. I havent seen any EWCM yet so dont think i have ovulated yet. I wanted to know how long do you usually have between the LH surge and ovulation? Does it vary with age? I am 30. I ask because the earliest i have BD is tomorrow morning and i worry that it might be too late, but at the same time i havent got EWCM (ive been checking) so im hoping tomorrow morning isnt too late.