Hello,
My son is the same age and is doing the same things. He usually takes his morning and bedtime bottle pretty well, but the other two during the day are hit or miss. Sometimes I can only get him to take 3-4 ounces at those times. I was told that if they are getting at least 20 ounces a day, they are getting enough. Some days we cut it pretty close. On those days I put a little Poly-Vi-Sol vitamin supplement in a bottle. Also, he likes the Yo Baby yogurt, and one of the varieties has 45% of their daily recommended amount of iron. I would venture a guess that your little guy is about to get a tooth or two. My son has 5 teeth and each time one breaks through, he is fussy and doesn't eat well for a day or two. Another thought is that they are becoming so active at this age, they are just too busy to settle down for a bottle. I just keep at it...and some days I feed him small amounts more frequently if I have to. I'm with you though...first time mom, just trying to figure all this out! Good luck :)