Hey ladies. So this is my first time cycle using a OPK. My husband is gone for the week training and will be home friday so I am hoping I dont O before then!

I took the first test sunday-very light test line..and it was getting darker slowly since..but today it was hardly even there?? So my question is does it usually get darker every day until the LH surge when you get your two dark lines..or can it go from hardly one day and verry dark the next??
I am still trying to figure out my cycle..I have only had 2 AF this year with the m/c and all so it has been kinda crazy...my cycle used to be about 33 days..if it is still the same i should be O anytime...hopefully not before hubby comes home!!