I got off work and started the car and waited for it to warm up. After I warmed up the car a bit, I released the e-brake, pushed in the clutch all the way, and when I tried to shift into first gear, it seemed like it wouldn't go all the way into gear; it felt like something was blocking its path. I released the clutch, and repeated the steps. Finally, after a minute or so, it went into place; I think I added some force.

What's happening here?