Having problems with upload connection

Hey SevenForums! So not long ago, I decided to start streaming some of the games I play, as I find it very entertaining watch others, so why not try it for myself? After trying it out, I found out it was very laggy, which is really wierd, when my internet connection is supposed to be 40/40 or 30/30. When I then went to the connection speed tester from my provider, it showed 35/5, and I was...