Is this depression

I never suffered post partum depression with my first and was doing really well after this guy was born on wednesday well, this morning my hubs went back to work and I was at home with the baby, my 2 year old and my MIL. I broke down crying when he left for work, tried to take a nap but woke up to my 2 year old being so obnoxiously loud, whining for a yogurt on repeate, the house a disaster. I freaked out on her and gave her a yogurt and yelled to leave me alone! To a 2 year ols, I yelled at her to leave me alone. I've felt like crap about it and cried all day long off and on... I finally took a percocet that I was given for pain with the stitches around 3 and have been feeling much better.. I don't know if I'm just overwhelmed with two babies or if this is the beginning of depression. Has anyone gone through ppd?