Stop in for a cup of coffee

I feel like I worked that many hours this week. But I only worked my regular shift. We are helping cover 3rd shift. 2 of us on second - one stays 4 hours over every other week. Leaves us short first half of our shift if we only do 8s. So last week I did 10s and co worker only had first 2 hours on his own. I thought he would do same. Nope. Was on my own first 4 hours for 4 nights. Jerk