Check with your ISP in the morning. Give them a call. Yesterday all day I was having trouble with my internet on steam. I would get in the server and after while it would lag and I lose connection. Steam would auto try but it wouldn't go through. Quantam advised me during game that the issue was not with my comp. or set up. It was with the ISP prodvider node that was down and affecting my service. It would re-route my IP to another server. hence everytime making me lose my connection. It went away today thank good and I haven't had anymore trouble. If it did continue I would be calling my ISP provider immediately. So try that. Good Luck