A C&P but these are the symptoms:
Stomach upsets, swelling, diarrhea or constipation
headaches
Changes in anxiety or depression or food cravings
Breast swelling and tenderness
Anxiety or depression
Fatigue and trouble sleeping
Joint or muscle pain
Stress, irritability, mood swings
Lack of concentration
Sugestions as to what causes this are limited and also readly available inforamtion is out there for you to find your own treatment. Have you had this all the time you have been working? Do you know what causes your pre-post menses?
An ohs is a pre-employment evaluation isnt it? What are they only doing one on you now or is it to assess whether you are fit for working where you do?