My baby stopped talking, smiling, rolling HELP

Merry Christmas everyone that celebrates. So this past week I noticed that my 5 month old soon to be six month old son hasn’t been talking, smiling or rolling like he used to. It’s so concerning because I’m not sure why this is happening. Has this happened to anyone? Please help me y’all because my anxiety is through the roof. FYI his sleeping pattern is disgusting! He’s still suffering from major sleep regression so waking every hour throughout the night. I’m solely breastfeeding and have introduced him to oatmeal which he eats twice a day if he decides he likes it in the moment. Any and all tips and comments are beyond appreciated and welcomed. I need to ease my nerves before I don’t make it into the new year.