5 Month BF Trouble😫

So I just came up on exclusively BF my little princess for 5 months and these past 2-3 weeks have been pure hell. She hasn’t been wanting to eat. I can only get her on for about 5 minutes or she just refuses to latch on all together. She will just turn straight away. I am super worried her weight will drop and I am also worried my milk supply has already suffered from her lack of eating. I really need some help on what to do! It has been really stressing and putting me down. I sometimes think of just giving up on breastfeeding because of this. Please please I need advice😥.