NFL's DeMarco Murray -- I Got Married ... And My Wife's Preggo!!!

Big weekend for Philadelphia Eagles running back DeMarco Murray ... who married his longtime girlfriend -- and then announced she's PREGNANT!!

Marco tied the knot to Heidi Mueller -- his longtime girlfriend and mother of his 2-year-old daughter -- at the Four Seasons in Dallas.

And during the festivities ... Heidi also announced she's pregnant with their 2nd child!