the skin of my glans is dry. It usually appears after I masturbate. After a while, it irritates me on the right side of the glans when the skin is dry, it is approximately 1 cm irritated area
Are you using any form of Lube such as Baby Oil or any other oil based lube? What is most likely is that you do not have the best circumstances going on for the dermatological health of your glans, and probably the rest of your penis as well.
What you need to be aware of is that during masturbation there is a whole lot of friction going on with the skin in the glans and foreskin area of the penis in particular. If there is anything present on the skin that can act as an irritant in these circumstances then eventually the skin will react to this. Obviously this is linked to frequency of masturbation, the length of time you masturbate on each occasion, and critically, whether you wash and fully dry the entire penis skin after you have ejaculated.
The worst circumstances is to leave any trace of pre-cum and semen between the inside of the foreskin and glans of the penis. Particularly, if you are in the habit of falling asleep in bed after you have ejaculated. If you do not fully clear away all fluids, and check several times up to 30 or so minutes after ejaculation further fluids can become present at the tip of the penis, and it can be these kinds of circumstances that can cause real harm to the skin.
You need to look at what cleansing agents that come into regular contact with the glans and foreskin area of your penis. Switch to dermatologically safe shower gels and suchlike if you regularly shower. When you wash your penis do not use soap, running water, rub with the inside of your hand, immediately pat dry with a towel.
Then, as I have alluded to, think about what else is in regular contact with your penis and foreskin area? The type of lube you use, if any? If you are sexually active, do you use condoms?
The best guidance is to get your penile hygiene regime right first, then look at getting plant based extract oils to use to hydrate the skin - such as Coconut Oil and Aloe Vera Gel - you may need to try several different ones to find the one that suits your skin type best - try each one for 4 or 5 weeks at least to see how your skin reacts to it …