lucy, I would seriously recommend not stressing or thinking about adding in extra supplements until you've had a couple of cycles.
I only say this from experience. I was Uber Anxious initially once I had my Mirena out and started charting straight away. My first cycle I had a 28 day cycle and I only had a 10 day Luteal Phase which was so distressing and was planning to get loads of supplements in. However, my 2nd cycle was a 32 day cycle with a 13 day luteal phase which just showed I should never had panicked my first month as my body was clearly sorting itself out post Mirena and it takes, unfortunately, a bit of time for it to do so. I know that's not great when we're so impatient for our BFPs but thats the way things are.
I did try some low dose Soy Isoflavones (which I got from tesco) this cycle. People use this as a 'natural' form of Clomid to promote ovulation (in case of those with PCOS who dont ovulate/ovulate irregularly). I dont have PCOS, so m intention was to try and bring my ovulation forward. It hasnt worked at all. But I dont need to take it really, as I definately ovulate according to my chart and the fact I get blinking painful ovulation pains every month!
I also tried some Vitamine B 50 complex this month because although my LP was great last month, I did have a bit of spotting. However, I had to stop it after a week as I had terrible side effects. However, there are plenty of women who take it with no side effects.
What I suggest, after going through such stress and trauma over the past 2 and half months is to try and calm down a bit, stop being too impatient and try and allow your body to settle down after Mirena. I may sound harsh but it comes from 2 and half months of pure and utter stress...which doesnt do ANYONE any good if they are TTCing as high stress levels can hinder conception.
Are you charting? I think that is seriously useful, particularly early on in your TTC journey. It will allow you to learn about your own body and see where your fertility patterns happen. Once you've given it a couple of cycles to allow your body to settle down, you may identify a problem that may need a supplement. However, you may find your fertility patterns are fine and dandy and you dont need the extra help some ladies need! Check out Fertility Friend, its a fascinating site!
Hopefully you are taking your folic acid regularly, which is important for fetal development and prevention of neural tube defects like spina bifida.
Good luck!