Excessive lag on LAN direct connection game

When playing a LAN game via direct connection to my husband's computer, I am experiencing excessive lag when performing certain tasks, such as opening chests, which now takes about 20 sec for the process to occur. It is usually immediate or with a second or so. Also, when I log in, it shows me at zero level and then takes about 5 secs to put me at correct level.

This started today and is not happening in my single-player game. I played with my husband last night and everything was normal. I also restarted my computer and downloaded the latest java update so that should be fine as well.

Please help!
Shannon