i usually take opk test around 8pm. so if u think u r ovl on 22nd. just test around 8pm (not to take any fluids atlest 2-3 hrs b4 u test). still the result is -ive. then test the next day. its all depends on ur CD's. my cd's r reg 28th so i ovl on cd 14th. i get positive on cd 13th. BTW i would recomend you to use a clear blue easy digital opk' coz its easy to read. strips sometimes get confu. Good luck :) n' give us update.
What cycle day are you today (with day one being the first day of your period)? And how long are your cycles normally?