@ysmina-- Before going the route of supplements, why don't you try to increase collagen naturally with the foods you eat? Our body produces its own collagen. This production decreases as we age, but we can help promote it with what we eat.
Vitamin C, for example, has been proven to boost collagen production, so you can add more vitamin C rich fruits and vegetables to your diet. Same is true for foods rich in antioxidants and omega 3 like flaxseeds, red and dark green fruits and vegetables.
I also found out during a skin care workshop recently that turkey and chocolate is also excellent for collagen production. The type of protein in turkey meat and the antioxidants in chocolate help us produce more collagen for our skin. Avocado oil applied topically is also good for this.