Balding or Big Forehead? (photo)

It difficult to make a good assessment based on your photos. There does appear to be some thinning but it's essential to perform a full history and exam. You're in a good position to start preventing additional hair loss if it is beginning. There are many options available. Propecia is a common mediation used to block dihydrotestosterone, which causes hair to miniaturize and leads to terminal hair loss. This has a low side effect profile and is generally well tolerated. 50% of men see a stabilization of their hairless and 50% see additional growth. There are a various biostimulatory injectables that can be used from PRP to micronized fat grafting that helps stimulate and prevent hair loss. Hopefully you can prevent the need for grafts but if you can stabilize your current hairline then you could consider grafts in the future if you're looking for more density. 

Analysis of your situation is best done by an in person consultation based on several factors.
Temporal recession is a normal variant of hair loss seen in most adult males.  Some patients opt to create a more forward looking hair style based on preference.  
Trichoscopy can help determine if miniaturization is taking place and the extent of it anteriorly.
Genetic testing and history can help determine your future hair loss plan.
Your hairloss solution can vary from evidence based medical therapies to conservative hair transplant in certain situations.   Best Anil Shah 

At your current age and given your hairline pattern, Norwood 2 classification, I would recommend non surgical options.  Propecia, is a medication used to assist in maintaining your current hair count.  It may have side effects though and I would recommend you speak to your primary care physician prior to beginning therapy.  There are other options as well including Minoxidil, a solution that assists in increasing the blood flow to the scalp, thus improving hair growth.  Injections using Platelet-rich plasma may assist in slowing the progression of hair loss and may even assist in hair growth.  Light therapy is used and in some circumstances may encourage the dormant hairs to actively grow.  This light therapy does take numerous visits to your clinic that provides this option and it may be difficult to stay on track with the treatments.  If you see that your hair loss continues, I would then seek a hair transplant surgeon and ask him or her their thoughts on transplantation.  I hope this helps!

Without an in-person exam, it is difficult to say.  Cutting the hair shorter will definitely make the hair look thinner and appear as though there is less hair "mass."  That being said, family history regarding hair loss can also be helpful.  Finally, it is important to recognize that an adolescent male hairline is not the same as an adult male hairline, and some degree of frontal and temporal recession is normal and age-appropriate.
A consultation with a fellowship-trained hair restoration surgeon would be helpful.
All the best,

If you cut your hair short, it may look thinner.  This is just common sense, right?  If you always had thin hair and a high forehead, it would look worse with a shorter hair cut, right?  If you believe you are balding, you should see a doctor for an examination.