I'm having severe pains on the left side of my stomach?

Okie dokie, so I received my monthly gift (lol) yesterday when I woke up. I felt fine, did my daily P90X ate normally (a lot of protein) and went to bed. Today I woke up and felt fine, but about 3 minutes after waking up I started to feel a sharp pain in my right side (between my rib cage and hip). I could barely move without having to double over because the pain was terrrible. I went back to bed and woke up about 3 hours ago.. The pain right now isn't too bad, but I can't do a trunk twist (just twisting my upper body) to the right side without feeling like I'm about to tear something in my left side. It feels like something may be like right under my ribs on the left side but I don't really know because I've never felt this before. I didn't do P90X today (this would've been my 4th day) because of pain. I'm upset that I'm a day off schedule, but it was just yoga... And ideas of what's wrong with me?