A day at work can be long, that's completely understandable since it's the life of research. Yet still it's always fun to go to the lab, meet your colleagues and work. The reason is because the lab is very diverse, the students and the graduates are very open minded and outgoing. So overall it's always a good day to be at lab.
I have learned a lot of things from all my colleagues, from procedures and experiments to life lessons and future plans of research.
All in all, nothing is ever achievable if you don't do what you love otherwise it will never have any taste and no productive effort will be put towards it.