What should i expect for my budgies first clutch ?

Ok I have two budgies of course one of both gender,they are both young but I want to gather as much information as I can about them before I breed them I have not added a nest box and will not until about 5 months. Also I have an additional question, my male budgie has shown much intrest in his partner and has even regurgitated into her but recently (the past week or two) she has been running him off afterwards and now it is two the point where he won't even try anymore. They do preen eachother but I want to no if it sounds like they are bonding or bonded because I really want them to breed. Thanks