4 year old tired all the time

I don’t know if I’m just overthinking it but she went from never wanting to take naps at the age of 3 to now asking for one. And she looks so tired all the time with bags under her eyes. She sleeps through the night. I will say she does not eat right as much as I want her to. She refuses to try fruit, veggies and some meats. It’s very difficult for me to get her to eat what I cook. So I know she might be lacking some vitamins.. I’m going to buy smarty pants gummies for her this week but I already know it’s going to be hell trying to get her to eat them. She doesn’t like anything kids normally eat at this age. No juice no candy (which I am not mad about!) I guess what I’m asking here is is this normal for a 4 year old? To be tired and ask for naps?