Your skin might be affected by acanthosis nigricans which is identified by dark patches, even on the throat and joints. Being overweight and having high blood pressure are risk factors for this. The treatment is to lose weight and control the BP, as a result, the patches can be healed. Follow a healthy diet, exercise regularly, and be consistent with your prescribed medications to control your blood pressure.

Since you missed tetanus vaccination after second-degree burns, you are at risk for tetanus infection. The symptoms may be visible within 3 to 21 days, usually at 7 to 10 days. Tightness of muscles, spasms in the jaw, and difficulty in swallowing are some of the symptoms that one may experience. If you notice these signs, you should seek medical attention at once. The tetanus vaccine can, however, be administered after an injury to avoid infection. 

It is important to take care of puppy bite­s and scratches. These can cause­ infections if not treated right. Look for signs like­ redness, pain, swelling, or pus at the­ spot. Make sure to wash the are­a well with soap and water. If it looks infecte­d, like more redne­ss, warmth, or pain, contact your doctor for more checks and tre­atment. Puppy bites and scratches are­ common, but they can be serious. It is best to cle­an the wound and watch for signs of infection. Don't wait if it gets worse­. See a doctor quickly. 

 The prime reason for this is mostly the excess oil production on your skin. Stress, hormonal changes, and the fact that you don't clean your face properly can worsen it. To boost your skin, follow these suggestions: wash your face often with a mild cleanser, keep your hands off your face, and eat a balanced diet.