Breastfeeding makes me feel bad??

Me

Does breastfeeding make anyone else feel bad? I have been exclusively breastfeeding my 4.5 month old since he was born. I often feel weak, shaky, kinda nauseous, and just off (especially in the mornings). I’ve been to the dr, my blood work was normal, and I take my prenatal vitamin still everyday. I also eat and drink constantly.

Has anyone else experienced this?? Wondering if my body just doesn’t like the hormones or what!