It is hard to diagnose your balding without a professional examination. If you are worried about hair loss, you should visit a dermatologist who is a specialist in hairs loss problems. They can analyze your condition and give you optimal care.
 

It depends on the extent of the damage. If the wound is mild, cleaning it with a mild soap and water will promote healing. For serious cases, you should head to a dermatologist or a plastic surgeon with expertise in breast reconstruction. It is also wise to seek medical assistance to avoid possible complications.
 

It seems you are facing a heat rash which is a common condition. Your skin gets too hot due to the sun and it can make your skin red, itchy, and throbbing. After a time, you should avoid wearing clothes that are too tight. Make sure to wear cool, loose-fitting clothes. Moreover, always keep below clean and dry when there is a chance of heat rash. Calamine lotion can also be a good option to use to relieve the burning skin. Drinking enough water is important. 

If you put salt (NaCl) on a cut it may hurt a bit. The reason for this is that salt is able to kill germs. Therefore if you rub salt in a wound it will only be painful temporarily. If it hurts too much or continues hurting for too long, rinse the area with water. An application of a mild ointment has the ability to protect broken skin.

The most common reasons behind this are allergies and skin irritation. You should pay attention to the products you use because they should not contain any harmful ingredients. To fight against this problem, moisturize well and avoid using soaps and chemicals that are too harsh.

Stretch marks are lines that appear on the skin when it is stretched a lot, such as during pregnancy. They may start as red or purple but gradually fade to a lighter color. To help reduce their appearance, you can use moisturizers or creams containing retinol or hyaluronic acid to keep your skin hydrated and healthy. Additionally, maintaining a healthy weight and drinking plenty of water can also help. However, remember that reducing stretch marks takes time, so be patient and stick to your skincare routine consistently.