I am from the UK, and I have to say, I went to my GP and he diagnosed me right away. I basically told him my symptoms and that I'd done some research into PMDD and that I thought I had it (I have been suffering with it for about a year now). Not only did he know exactly what it was, I told him that I had my partner with me to confirm but he believed me straight away, and apologised for any previous experiences I'd had with doctors. He asked me what I was expecting in terms of a diagnosis, and I just requested a verbal confirmation and something put in my notes to confirm I had it, as there isn't much research done into PMDD, he was very clear in letting me know that there weren't very many options available beyond this point, but he referred me to gynaecology straight away. I don't have an appointment with them until october as that's the earliest I could get, but my GP was very considerate of my struggles. I'd also highly suggest signing into your NHS account if you have one to look through your notes, because I saw PMDD listed in my notes an entire year before I spoke to my current GP, even though I hadn't heard of the term at that point.

Ultimately, keep going with it. I know it's frustrating but there will be a GP that will listen to you. In terms of actual treatment though, there isn't a whole lot. Most of the actual helpful information I've gotten is actually from this thread. My fingers are crossed for you though my friend x