I found out the problem. It wasn't my internet, it was the router. Was searching on dslreports.com's forums and came across quite a few threads about the same problem I was getting. Performance degradation. Slow web speeds, but normal direct DL speeds. The main thing that clued me into it being just the router was when I tried to login to the router itself. Was getting the same results as with web pages. Took forever to load, or wouldn't load at all.

So a temp fix is to restore factory settings every time the router decides to have mood swings.