I'm 19 I'm on my 3rd month using opks! First two months I was using clearblue advanced, ( I don't really care for them I think they were not accurate) now I'm using first response digitals I started testing 5 days after I started af on 1/30 I've been testing once a day getting all no (no surge) while using cheapie sticks as well just to be sure! Me & my so have been <a href="https://play.google.com/store/apps/details?id=com.glow.android">tracking ovulation</a> for my almost three months this month will be my third!! We are on our first month of fertilaid too!! Girls have any tips? :)