Breast feeding harder than I thought

FTM 17 days postpartum and breast feeding is much harder than I thought. It's honestly not enjoyable. The first week my nipples became raw, bloody and scabbed. I got a nipple shield and they've healed, but I can't nurse without it. The past few days I have had to supplement with formula, maybe 2 bottles a day, to give my boobs a rest. He never seems satisfied from me and constantly wants to be on my boobs! He nurses for about an hour each time, every 2-3 hours. I feel like my life is nursing and I'm exhausted from it. Mentally, I want to throw in the towel, call it quits and break out the formula full time. But I haven't done that because I had my mind set on breast feeding this whole time and I feel like a failure giving up. I cried when I gave him formula last night to give me a break. I don't know if he's getting enough from me, or if he's satisfied, I get aggravated with how long he nurses and how constant he nurses. I also pump here and there but that still makes me feel so confined. I feel like a bad mom. Advice please. Does this get better? If so, when? Should I feel bad for wanting to give up?