What Causes Delayed Periods And Bulged Stomach Along With Sore Breasts?

Hello, my name is aida I got a depo provera shot in january got my period in late january, light spotting and also in march and april i have not yet gotten a period this month. I have gained some weight and my belly has gotten bigger and firmer. I also have been feeling this strange movements in my belly that i dont know if they are gas. I also noticed today that i have that linea nigra and the spots on my areola and my breast are extremely sore. I took a home pregnancy test and it was negetive. Can I be pregnant?