My Cadillac is stallin! Need Help!

I have a 1992 Cadillac Sedan Deville, 143,000 miles on it. When I turn it on it the mourning it takes a while for the transmission to catch. And just yesterday when I was at a light and when it put on the gas the car just stopped while the engine was still on then I put gas to it then it jerked and took off. What could it be rather then morning sickness which could be an internal leak. Or does it need to be flushed out already?