You Uncle just advised and not forced so it is still all upto you. You Uncle is done with his Course and now he is doing his job. It is you who will face the real world from now. If you are not interested in Medicine then why should you opt it. If IAF gives you thrills, if it boosts your Adrenaline and if you really want to join Indian Air Force then please go for.

"Opportunities comes once in a lifetime.....