Can your hair change when you get older?

:3

I noticed this 2 or 3 years ago but it wasnt that noticeable my hair naturally straight and now its has weird wave to it I usually never used blow dryer but now I have to if I dont want the waves I blow dry it it comes out straight and it will stay like that until the next time my hair gets wet and I let it air dry

I havent done anything differently from now to them when I air dry it