Is it safe to take St John's Wort, Evening Primrose Oil and Iron Supplements?

I don't take the iron all the time, just for a week or so before my period as I get bad headaches and migraines and thought this might be due to losing iron around that time of the month. Same with the evening primrose oil, take it for a couple of weeks each month to help with physical aspects of PMT. I am a rather anxious/stressy person and I am prone to bouts of depression and my mum has been suggesting St John's Wort to me for years. I'm going through a stressful time at the moment which is set to continue for a few months so I thought it might be time to try the SJW. I don't take any other medication apart from paracetamol sometimes and occasionally something stronger for the migraines (Migraleve or Immigran). I read that SJW can reduce iron absorption, so is it ok to keep taking the iron supplements to counteract this? I'm also worried about the effect on my liver from taking a combination of supplements. Should I take them at different times of the day to allow my body time to process each tablet? Thanks for any advice you can offer.