I Am 11 Days Late On My Period. I Have

I am 11 days late on my period. I have been feeling nauseous for the past week. I spotted from like the 28th- 4th of this month. My actual period was suppose to come on, on the 11th. This doesn't mean that I could be pregnant could it? I was on birth control so I haven't even started a new packed because it hasn't came on. I took to test and they both was negative