Guys, I think I've fixed the memory leaks. It could be two things though: The first thing I did was tick the box on the technic launcher to increase permgen size, also this whole time I built my house in the redwoods forest biome and I noticed that when I left my house to explore or what not the memory usage decreases quite significantly (from about 5gb to 2.5gb)
@CNxHawk I might've given you the wrong info on what to replace xD Here I followed this tutorial. http://www.minecraftwiki.net/wiki/Tutorials/Update_LWJGL