Breastfeeding and supplementing

We had a 3 day checkup with the doctor today and he has lost 1 pound. I have been non-stop breastfeeding since he was showing hunger cues but it's not enough. My doctor says I have to supplement to get his weight back up. I feel like such a failure. I was hoping with my milk coming in the supplement would be too much. However this is the first night doing it and he is eating the formula and not so happy on the boob now. How do I prevent him from wanting the bottle once I start producing enough since bottles are easier to suck then a breast?