Yeh you need to see your GP. There are a few reactions people seem to get depending on what the problems are. You may get offered meds (which you need to be aware it's up to you whether you want to take them or not, but be honest with the dr there and then about that), they may say see how it goes seeing a counsellor or they could refer you on to a community mental health team or other service in the area. The problem with most mental health services in the NHS is long waiting times. Each area is different, but just don't get your hopes up that it'll be right away!

The ones you've looked at are private, which you would have to pay for but could start a lot quicker.