fear of child/myself/husband dying

I've been married for two years & I have an eight month old. I've been such a hypochondriac for probably 10 years but it was usually only about myself getting cancer but now I'm TERRIFIED of all three of us dying. I google information endlessly, I know about so many deadly diseases. I create scenarios in my head where I get the bad news and I actually bring myself to a point where my heart pounds, and my stomach feels so tight, and I often cry about it. I think about it everyday but honestly feel like the start of my period brings on the thoughts more than any other time in my cycle? it's out of control throughout my whole cycle, though. it ruins my daily life and I don't know how to stop googling. it's not only that, but I'm obsessed with hospital shows and that makes my fears worse when learning about new diseases.. anyone know how to cope? who do I see about this, primary doctor or OB? I feel psychotic..