The CD led is the light thats on the front panel of your CD drive (most have one). If it did spin it means likely it did try to boot from the CD. If it is an older CD drive it can happen that it no longer boots from a CD (a CD drive can go bad or have functionality issues fairly easy).
I did have some problems with my CD drive area before; that could be the case. Should I try a USB now? And if I use a USB can I still use the USB for future uses?