So unless my mind is playing tricks on me, there appears to be some kind of bug with how much you can carry. I may be carrying something, say a rocket launcher, I drop it to pick something else up, I decide I don't want that something else, but when I want to pick back up the rocket launcher, it says I have reached my maximum weight capacity, even though I just had that item a few seconds earlier.

What am I missing?

There are some possible reasons.
Have you used drugs to temporally increase your stats?
Have you changed your armor? The power armor gives you +3 str.
Look at your overall carrying capacity (25 + str x 25).

I think you can also overload yourself by, say, buying a metal armor.
The game only checks your carry capacity when picking up stuff.

Are you over the limit when carrying the launcher?

Have you been heavily exposed to radiation? That also can cause your stats to drop a few points.

Sorry all, I think I was just getting confused. Things seem to be in working order.