I usually get these “bumps” as well when I do not do one or more of the following actions   

I use an inferior brand of shaving equipment ( that is a good blade, and a shaving foam which is not suited for sensitive skin)     

I use boiling hot water; it must boil before you use them!

When I finish shaving, I immediately dry my face (with a clean towel) and apply a shaving lotion and a few drops of after-shave.

As I said, if I don’t do these thing I get these little red bumps.