A.B.
A friend of mine who is now pregnant actually took 4-5 pregnancy tests before one was positive, she went to the doctor and they said she was a month further along than she thought. Basically, pregnancy tests aren't always going to have the correct reading. I'd recommend either taking another test, seeing your doctor, or just waiting a month or two to see if you have another period. With my last child, I had a really light almost non-existent period and then missed my next one so that's how I knew I was pregnant.
Good luck and congratulations if you are pregnant! Children are a blessing!