Master Bedroom - Refinishing hardwood floors

Here's where I began trying sanding for the first time, 3 different grits of sand paper for each tool (drum sander and edger....didn't care for edging, it's a back and leg breaker).  Also, replaced a couple boards in my room because they dipped really bad and also the previous owners tried to fill them with something...looked like wood glue to me.

The first swipe using the drum sander.

Boards I replaced

One last before I stain picture

After staining and 3 coats of polyurethane