First of all........Stop eating like a school girl, lol. Seriously, 1 can of tuna is absolutely horrendous PWO nutrition after limit squatting and deadlifting.
The thing is you just lift too close to bed time. Lifting gets you all mentally pumped up and releases endorphins and you're just too "amped up" to sleep so soon after a workout. If your schedule only permits training that close to bed, then you do what you have to do. I'd drink a quick PWO protein shake.....take a nice relaxing shower...then eat a proper meal (1 can of tuna is not a proper meal).....then wind down (read, play video games, jerk off, whatever relaxes you, lol) and go to bed.