In a match... kind of... and there are some serious issues

15 minutes in and highest cs is 44. Takes about 3 seconds for a command to respond and game shows about 100 minions in each lane because they don't disappear when they die. No one can do anything. Looked at all the forums and it looks like my match is the only one having this issue but all 10 of us are experiencing this.

Any idea what to do?