There is always a bedding in period with a new course, learning about how things are marked, how the different tutors mark, etc. The 48% has been a shock and the tutor has clearly decided to hold you at a fail rather than giving you a pass grade of, say, 50%, so your mission is to work out why - you need to dissect the feedback and work out what went wrong. Hopefully, there will be something obvious which you can fix next time round. A bad mark does not define you, no matter how much it feels that way. Treat this as a learning experience to move on from. Come back if you want to chew over the feedback.