Thrush in 3rd trimester

TMI warning

I’m 30+2 weeks and I definitely have thrush like 1000%, I’ve had it before. Itchy, red, sore and discharge. Do I need to actually been seen by a doctor or can I buy thrush treatment in the chemist or supermarket like I usually would? I’m in the UK not America, it’s so sore and I wouldn’t get an appointment for days 😢😢😢