I am currently 9 days late on my period as of today. My period are regular and the only other time my period was late was because of stress and it came exactly a week late. This time it's passed a week, but I've been getting really bloated once in a while. I also have one sore nipple, it's my left one and whenever I touch it, it feels sore whether it's hard or soft. I've also felt out of breath a couple of times even though all I've done was stand and talk, and one night I was feeling very short of breath and I was just laying on my side. Keep in mind I am sexually active and the last time I was active was two weeks ago, and I did not use protection. I took a test on Tuesday which was exactly a week after my period but it came out negative but I'm still wondering what it could be. Any ideas?