spongebob squarememes

Yo, so I'm having this problem and my modpacks won't go on forge. It just goes on the normal Minecraft version. For example, (I use 1.7.10, 1.7.2 and 1.5.2), if there were a 1.5.2 modpack and I downloaded it, it would just go to Minecraft 1.5.2, not forge 1.5.2.