Win 10 Chrome - Desktop icons change smaller & folders keep getting grouped?

I don't know how or why but my desktop icons have changed to smaller different pictures and I'd like them back to normal size? When I r click, there is no 'normal' size to choose and pick from? I haven't added programs and dont play games. Another issue... maybe related is my downloads folder keep getting 'grouped' and I have to frequently choose, group by, none, large icons, sort by type... I don't know why it keeps changing. I'm not really computer guy but any ideas or help would be greatly appreciated. Thanks in advance!