Hi motherhendoula. I, too, am the mother of a future football player (as most strangers say...) He's always been off the charts for weight and just about there for height. He was 20lbs by 2 months, 30lbs by 6 months, and 38lbs at 12 months. He turned 2 in March and was 50lbs and 38"...as tall as most 3 year olds we meet. Especially in that first year and a half I can't tell you how many times I heard, "woah, he weighs more than my 4 or 5 or 6 year old!" Yes, yes he does. He was exclusively breastfed as an infant and didn't become interested in any food until well after 1 year. Even at 18 months he wasn't eating much with probably 80-90% of his calories coming from breast milk. As he neared 2 his interest in food started to increase and, although he still would probably rather nurse than eat food, it's probably about 50/50 right now. I'm in no hurry for him to wean and am quite fascinated by the child-led weaning process.
Anyone who has a child at one end of the spectrum or the other is going to have a more challenging time simply because everything in life is compared. Our babies are always bigger than everyone elses simply because out of 100 babies, ours are the 'biggest'. There has to be one that weighs the least and one that weighs the most and either of those will likely be a very different size than the baby in the middle because there is a wide range of people in the world. I have really had to sort through many mixed emotions of my own over this - especially during his first year. Some people thought he was the cutest, chubbiest baby they had ever seen and just adored him. Others were downright mean or rude about his size and made me feel very, very insecure. While I am on the thin side and live a very healthy lifestyle, my husband is overweight and I know that made things more of a concern to him from time to time.
But what I always came back to was to ask myself, "is he healthy?" Being healthy is SO much more than just about weight alone, especially for babies who use up fat differently than adults do. When it came down to it, I knew that he was getting the very best in the way of nutrition, was active, was meeting and exceeding all of his milestones, and has always been a happy, secure, and emotionally healthy child. His doctor has never had reason to be concerned and I knew I shouldn't either.
I feel like I finally found my peace about it all maybe 3 or 4 months ago. That's when I stopped obsessing over his weight, over what others thought, over when he'd start to thin out, and over worrying about if he was nursing too much/not eating enough and so on. I have concluded that he will probably grow up to be a very tall, strong built man, and that his body knows what its doing. With each month that goes by his energy only increases (as is typical in a 2 year old) and I can see a big difference in his size from even 6 months ago. He still wears the same size clothes that he did last summer (4/5) but is a lot taller.
Your job is to offer a variety of healthy foods, model a healthy lifestyle, model a healthy body image, and trust his body tell you both what it needs. If you are concerned that there is a medical problem contributing then start by getting that checked out. But if that has been ruled out I'd say stop worrying about his weight and focus on having fun & living well. =) It sounds like you are doing an awesome job of working on your own health (way to go!!) and your son will follow suit. Your lifestyle is what his normal will become so just keep challenging yourself to learn more and do better. I'm amazed at how much I've learned about real nutrition in the past year because of wanting to set the very best example for my children. I've found that, for me anyway, the more I immerse myself in quality info about healthy living the easier it is for me to do and the more excited I get about it. Some good movies I've seen include Food Matters, Hunger for Change, The Beautiful Truth (although slow, had good info) and Fat, Sick and Nearly Dead. Also, here's a website I've gotten a lot of resources from: http://www.westonaprice.org/.
Hope that helps! If nothing else, at least you know there's someone else out there who gets where you're coming from and has a big guy who can someday play on the same football team with yours.