I think you should get to the doctors. Are there any red patches on your breasts? It sounds as though you may have mastitis. The normal advice would be to breastfeed loads but I'm not sure you want to start bfing again if only temporarily? You certainly should massage them, hart showers and paracetamol for pain relief. But go to the GP!
But with the symptoms of tired, aching, hot and cold at the same time, irritable, and the soreness, that is all typical for mastitis. Mostly you can get rid of mastitis by resting loads, drinking plenty of water, massage and bfing loads, but sometimes antibiotics are needed. I reckon you should see the doctor, the hot and coldness sounds like you've got a temperature and that does need to be checked by the GP during pregnancy.