You are under a lot of stress. Also I hope you will forgive me on this one as am only a mere male your monthly cycle. I also hope it doesn’t cross religious and cultural boundaries. More of an observation then experience but have found a lot of women mentioning there monthly circle impacting on there symptoms.
Main consensus is birth control pills seem to help. Doesn’t seem to be all of the birth control also doesn’t seem to help all women but worth a talk to your gp I think at any rate, Are a few posts on in the archive about it. .
Also quite a common post among women with a few mental disorders on the net. Depression, SZ, Bipolar, borderline personality disorder etc.
Being under stress with a new job and going through your monthly cycle would be a great deal for anyone to go through, even a mentally health person. Something you have a right to mention to your boss. Even if a slight off handed comment, ie just going through some lady problems. If there is no understanding. It’s the bosses problem not yours tbh.