How to see the sights on a Sunday

I’m going to have to come out against sightseeing on your own. It does let you see what you want; For instance, I spent 45 minutes watching the canal locks. But on the whole it feels empty. There are no surprises. All I’ve really been doing is taking pictures of architecture and I don’t think I have any pictures of me.
I did see the Notre-Dame Basilica. I even went inside. I take it as a good sign that I didn’t burst into flames crossing the threshold. I decided not to push it and skipped mass.
I have been staying up too late when going to parties; 5:30 last night. This is playing havoc with my body.