I try to keep some perspective on things like speed and distance-when I first started riding regularly (in May) I barely made it around the block the first day. Literally. I was hurting so much I had to get off my bike and I pretended to look at my brakes as I crouched down gasping for air.
Now 6-10 miles 4 days a week (40-ish miles /week total roughly) is what I'm up to so I can see improvement. I have to remind myself that my base goal is to take a year (at least) to get in shape enough to do long multi-day rides.
At this stage I go by a weekly average more than daily, and I tell myself that in time I will be going further-I just have to be patient. I don't gain anything if I get injured and at my age, it might not take a big injury to set me back.
I'm also looking forward to getting a better bike and I hope that will make a difference.
Thats why I'm glad I found this forum-its a great place to learn and share!