I recently got medic up to level 5, which entitles me to spawn with body armour, making it my number one choice at the beginning of the game.
However, the medi-gun isn't exactly the strongest weapon, so to get around this I save up for a crossbow or eventually even a grenade launcher in the later levels.
Will kills with the crossbow and grenade launcher level up my Sharpshooter and Demolitions perks, respectively? How about if I use my pistol for head-shots (Sharpshooter), or buy a flame-thrower (Firebug), or a AK-47 (Commando), etc?
I'm wondering if I could still level up my other perks if my team needs a medic role.