Speech regressing?

My little man is a year old in a few weeks and his speech seems to have taken a few steps backward lately. About a month ago he was clearly saying Mum, Dad, duck, quack, guitar, giraffe, hi, bye, help, yes, & gone, amongst other words that weren’t clear. He’s slowly started replacing all of these words with a “ch” (as in Loch Ness, not chair) sound.

He still says Mum and Dad, and sometimes says duck still but mostly everything is just “ch” whilst pointing.

Should we be worried? Is this normal?