A not-so-long run that felt like a long run

Yesterday, I took advantage of a busy kid and nice weather and ran while my son was at a birthday party on campus.  Since I don't get back to campus much, I decided to run around campus.  It was a tad strange, because there were groups of people doing the stuff groups of people do on university campuses.  I was about the only jogger out and about, which was a little strange for having so many people around.  It was a very enjoyable run, though.  I ran about 4.5 miles, the longest I've run in a long time.  I know I have to increase my distance, though.  This felt like a long run, but in the scheme of things, it wasn't very long at all.  I have a 12.4 mile run to prepare for in June.  So, I have a lot of work cut out for me!