Ok....my car started running extremely rich and evertime i reved it up i would get like a flame throwing out the exhaust...??????

So i decided to change the sparkplugs on the car....and a new battery also.....Now the car wont start at all......seems like the firing order .(does anyone know the firing order???)is off or something because ill try to start it but the engine doesnt even try to turn over at all?????

Any suggestions or idea what could be wrong???