I Was Searching For A Medical Opinion On Whether Or

I was searching for a medical opinion on whether or not I am experiencing implantation bleeding or just a lighter period.

I got my last period around October 10th-October 17th, usually lasting 5-7 days. A week and a half to two weeks later I had sex on the 27th. The first condom we were using broke when he was pulling out at one point. I heard it happen and made him change it right away. The next condom was a little older, but didn't break. Also, I am currently not on birth control. Because of this I am always very paranoid and stress about whether or not I'm pregnant, even when I use protection.

I have been expecting my period this week or next week because it is VERY regular. On Saturday November 12th I went to the bathroom and realized I was bleeding. The bleeding wasn't as heavy as my usual period, however it was enough to fill 2-3 super plus tampons a day, which is only 1 or 2 less than usual. At one point I even bled through one. The color was bright red, but my regular cramps or sore muscles didn't accompany it. I've also been feeling really nauseous, but I don't have tender breasts or headaches. The bleeding stopped yesterday afternoon, lasting a total of 5 days.

At this point I'm just concerned that this could just be implantation bleeding and not actually my period, which I initially suspected. In your opinion, how likely is it that I am pregnant and how long should I wait before taking an at home pregnancy test?