So I have been having some symptoms of pregnancy but I don't want to assume anything.
My last period was on November 20th, lasted about 5 to 6 days. I was supposed to get my period on December 18th but never got it. I did have unprotected sex December 20th through the 28th with my husband who came home from the Navy for that week. I took a pregnancy test on the 2nd and it came out "Not Pregnant". Yesterday, January 3rd at around 9pm I had a dark brown spotting. Then today it's heavy and a dark red color, when I wipe it is light pink. There are some clots, so I am thinking it may just be my period. My cramps hurt but are bearable. I am not sure when I ovulated, but on my tracker it said December 21st.
So ladies, I need your help. Any of you had the same issue or have you had heavy bleeding and you were in fact pregnant?
Thank you ladies in advance!

Given that you had sex a little over a week ago. It would be near impossible for you to have symptoms yet. I'm guessing you were aware your husband was coming home around the 20th and that affected the onset of your period. This would be especially true if you were on birth control meds and stopped prior to your husband coming home.

But even if you are pregnant, there would be no way for it to physically manifest itself this soon. (unless you had sexual relations sometime between 11/20 ans 12/20). Taken a test on Jan 2 was a waste of a test.

I can't tell you the cause of what you were experiencing, but I'm almost positive it was not due to a pregnancy. I would wait until the end of January and if you still haven't gotten a period, then take a test.

It sounds like you're having an off period. It happens to every woman at least once in their life. Brown blood indicates old blood, blood that has been in your body for a while, and now your body is extracting it. The fact that it turned to red blood is indicative of a period.

Having said that, some women do bleed throughout pregnancy and mistake it for a period.

You're testing too soon. It takes the sperm at least a week to get to the egg, fertilize it, and then the egg needs to travel and imbed itself into the womb. That's when pregnancy starts. It does not start the day you have sex, so having symptoms a week after sex, is not possible. You wouldn't even be pregnant by that time.

Wait another two weeks at least, then test using first morning urine. If that test is negative, wait for your next period, see how it goes. If you miss it, or it's off (lighter than usual, not as long as usual), than test again. If that test is also negative, than see a doctor for a more accurate blood test.

Good luck. :)