I'm worried i'll get brain cancer from excessive smartphone use and due to the fact that we don't have enough research on the subject since smartphones have only been around roughly a decade. is this a real concern or am i just overreacting?

There does NOT appear to be any conclusive or scientific evidence to support a relationship between cell phones and brain cancer. If you have concerns, you could connect head phones or ear buds, and keep the phone itself at a distance.

Agree with Dr. Mechanic. You can reduce your risk of cancer by adopting healthy habits: Eat a mostly vegetarian diet, avoid alcohol, tobacco and street drugs, avoid excessive exposure to sun, get HPV vaccine, exercise 30 minutes each day, drink enough water so your urine is mostly colorless.