It depends what you mean by “rather worried”
Do you mean “rather worried” so you might check in a little more often with their teacher, discuss strategies to support spelling at home, and focus a little more time on spelling?
Or do you mean “rather worried” in that you are demanding diagnostics/hiring a tutor/putting extra pressure on your kid?
My daughter also struggles with spelling. She’s too young to be diagnosed as dyslexic, and I’m not sure she even is dyslexic to be honest. We do some extra fun spelling tasks and games at home to reinforce her learning, and her spelling seems to be improving. We get a note of her scores in spelling test at the end of each “block” (approx 6 weeks)
As a consequence, I’ve opted out of maths homework. I don’t want to overdo it. She’s young and I want her to have fun, too.
For the record she’s actually coping well with all other areas of language, so I’m not unduly concerned. Spelling is important; but not more important than, say, understanding sentence structure.