A numbered model K frame won't be hurt by +P ammo within SAAMI specs. An overpressure book load can hurt any gun.
K frames were being used with .38 ammo nearly twice the pressure of what we're calling +P .38sp today. You'll always accelerate wear by running higher pressure ammo, but +P shouldn't threaten a numbered model K frame like a 15-2.
Congrats on the gun, I have a 4" 15-2, thousands of rounds through it, including a whole bunch of Magtech and Rem 125gr +P SJHP, Win +P+ 147gr jhp and Speer Lawman +P 158gr TMJ. Still tight, still crazy accurate, great revolver.
Love the K frame snubby too...