Nervous and scared!!!

So af is due in 4 days but I haven't had any of my normal bout to start signs except my boobs have been super sore for a week now. Me and my SO have been trying for 3 yrs now, so every negative just about kills us ( started using preseed last month). I have 2 kids from past relationships and he has none but loves mine as if they were his but we want one more..... trying to wait to see if af is gonna rear her ugly head but really wanting to take a test but I know if it's negative I will be depressed and my wedding is 2 weeks and 2 days away so I don't need to get depressed but we want another baby so bad.... I just don't know what to do....