Exhausted

I sleep well (as much as possible,  with help of my pills) and I take vitamin B, C, iron (I have low iron due to my rigid diet). I also take my pills from psychiatrist. And recent week I'm so terribly exhausted,  that I feel like my body is in a swamp and I'm struggling to move, coordinate, I fall asleep or pace out even after a coffee. The pills I take are SSRI with fluoxetin. Is it possible to get depression despite taking antidepressants? Maybe it's burnout, or something else. I would like to do my favourite thing, for example finish my sci fi story with aliens, but I can't. It's all too much. Talking to people also feels harder than ever. It's nothing new to me, I get this experience periodically I can't say since when actually. I also miss a connection and have no friends and sometimes cry I myself don't know why. I'm sorry for this negative post. I also struggle with my joints (they ate somehow loose and more mobile so it's easy for me to get injury without hitting anything. My colleague suggested that I go to doctor but I know, I would get a sick leave and the perspective of my daily and weekly routine being destroyed is unbearable. So I hobble and keep going.