Honestly, they are being jerks to you, but you can kind of see a common thread here, and it happens a lot with newer players. I'm assuming they were fighting 1 vs 1 or something to that effect, using the reach of their weapons, footwork, and all of that. You probably ran in to help, but instead of coming from the opposite direction or giving your teammate enough room to swing like an experienced support player would, you cut him off and ran in the middle, blocking his attacks with your body and getting yourself killed. Instead of being helpful, they called you a noob. When I see new players do this, I often end up doing both.
Try to stay out of your teammates way while still getting in range of the enemy. I'm not gonna consider these intentional tk's but shit talking people like this after tks accidental or not is a good way to get yourself banned (because you look guilty), Spook and Troublesome.