Jebbe

Hi guys, I'm new here and need help with the problem stated in the topic title. I'm playing currently MCC Halo 4 on XB1, and I accidentally managed to restart a mission, I was supposed to go back to the last checkpoint... is there a way to go back, or do I have to play thru the entire mission again? I was like few minutes from the end of the mission, ffs how can I fail like that. -.- I tried to Google my issue, couldn't find anything helpful... thanks a ton if someone can help me out!