Come on, it is a holiday weekend, don't get upset about no responses to a post within 24 hours.
With regard to your question, it appears that you are just started your internship. You also have posted in the last few days about switching to psych. My recommendation is to wait a few months and see what you actually want to do and how FM might really work out before starting on the path to apply to any new residency. Yes, it is possible to change residencies, lots of folks do it. You won't get credit for your first year, you'll have to do all three pedi years. I'm not an expert on the issue of whether you can move all three years of federal funding over if you switch after a year, but regardless, it will not be a deal breaker if you are an applicant that programs want. It would be best to focus NOW on being an outstanding FM intern so that you can get great letters should you decide, once you decide, to change to whatever you decide.