Any good or bad experiences from nursing and then going to pumping/bottle feeding?

I’ve hit the 5 month mark and I want to make it a year but I just feel like I can’t breastfeed any longer. I can’t explain it but I feel like it would help me out mentally if I starting pumping and bottle feeding. That way she can still get breastmilk but I wouldn’t have to nurse her every time.

She is also pretty underweight and if I bottle feed her then I will know how many oz’s she is actually getting.

Thoughts?