Advice on Fatigue

I am 5 1/2 weeks in on my weight loss journey. I have been really consistent with IF. I have been eating at 12:00 and 6:00. I have also been really consistent with no sugar or flour. I have only lost about 3 lbs, but my clothes are definitely feeling more comfortable. I have really been feeling things like disappointment and patience! I have been following my protocol pretty strictly. I have heard Brooke say that she didn’t lose anything for 6 weeks, and that is what I am working towards . My question is that I have been feeling tired and not much energy. I have been having trouble with sleeping as well. I am so committed to this program, but wish that I felt better.