Help! I think my three week old son is eating too much!!!!?

I know a lot of people are gonna say this is bad but I had to do it with both my girls when they started wanting to eat hourly I put cereal in with there formula but I usually only did it at night. Or instead of 4 ounces try 5 or so and maybe he does want a binkie just a different kind. Or if it's his thumb he sucks on he may just be a thumb sucker. My 4 month old is when she's tired she cries and sucks her thumb. And at his age he doesn't really know to push the bottle away yet.