People holding my baby

Okay y’all I have been having more anxiety then my usual anxiety and have never been put on meds for it since I’m really good and handling it on my own. Okay but here is the the thing I hate people holding my baby other than my husband, parents and siblings. (Parents and siblings live in another state and only saw (baby) him around Christmas time) I get even more anxious when my husband’s mom holds him. She holds him for very long periods and doesn’t ever ask politely. One time just putting her hands out and towards me saying “k” gesturing it was her turn to hold him again she held him for an hour half and gave him back for only 5 mins and took him again. But ever since then it made me start having anxiety about people holding him. I honestly don’t know of how I can politely say no because I get so nervous to say it but I also get a bad gut feeling when people hold him for too long or don’t even ask nicely. How would be a good way to tell people no or take him back when I feel like I need to hold him again to calm my nerves?