Confused

Hey! Okay so me and my boyfriend have been trying to have a baby. We started having sex when I got off my period last month and been having sex everyday since even during ovulation and a week before my period was suppose to come I had dark brown discharge for about 5 days and I thought it was implantation bleeding. Then when the following week came and my period was suppose to come it didn't so I tested and it was negative? My breast have been sore , I've been light headed and feel like I have to throw up here and there. Can anyone tell me what's going on? I'm a week and a day late now.