Am I suffering from blood toxins?

Patient: Hello doctor.I’m 16 three days back I got allergy.Itching and when I scratch it leaves temporary bumps and skin gets red and after half an hour I get normal.The itching waves come all by sudden.Face,leg,arms in other mean whole body is affected.Now I look my leg it’s having dark blood clotted patches on like blood stopped circulating there and it’s not disappearing.Body gets little swelling.I have headache as well.I could not sleep at night.At night arteries and veins feel like something blocked and feel fatigues.Suddenly, when I get red patches on body although I’m scratching or not and feel so much heat and I feel like I’m in flames and after sometime I get normal again.This all never happened in my life.It’s for first time.Here at my place it’s cold and I don’t drink much water cuz I don’t feel thirst just two three sips in a day but now I feel thirsty in this whole condition.Today,I searched on net and I came up with one thing that it was same symptoms as mine and that is toxins in blood.Ya I felt like this.I consulted with doctor and I have to be injected for three days of allergy.She gave me allergic tablets but not relieved cuz it’s not only allergy it’s toxins in blood I guess.Please tell me what is my disease?is my blood in toxins?Thankx