What concentration are you using? If you are using more than a pea sized amount for your entire face. Then you're using too much. You should definitely start a moisturizer/ sunscreen because tretinoin will make your skin more vulnerable to sunburn.

The concetration is 0.05 and i dont use more than this. Btw i am using it everywhere apart from my forehead which is totally clear. So i should start using a moisturizer. Thanks but should i use it every day or every other one?

.05% is good. Yes you could use it every other day until you start to tolerate it better. Moisturizer in the morning, I have to stress that sunburn can become severe before you know it. Use sunscreen and don't tan. Make sure you wait 30 minutes after washing your face before using the tretinoin.

Alright i ve already bought a moisturizer and i ll follow your suggestions thanks!