Hi Daniel, I am 50 Kgs and 37 and believe me i am skinnier than you.
What you can do is exercise, Start Swimming - After Swim you will feel real hungry and you can eat Protein rich food.
Don't Worry This is normal. The most important thing i belive is "Break the routine way of life".
Hi Dan-
He's right you need to exercise (strength training mixed with cardio) and right after you work out make a protein shake...you should try a type of whey protein called BSN. They have really good flavors like cookies and cream and peanut butter. Blend it with a banana and peanut butter. Then eat a protein meal like chicken. Avoid junk foods and foods high in fat. Be consistent and I guarantee you see results. Hope that helps at least a little bit :)
Thanks shriram1 and nicole110 for your valuable suggestions.