oil light comes on when above 2000 rpms

changed oil to 15w-40 royal purple with KnN oil filter took for drive light did not come on. Got home looked under the car and was puddle of oil. oil pressure switch that controls light was leaking. the one on car had yellow insulation on bought new one it was brown. Installed new one now light and beeper have returned. If I got dirt in sensor putting in would that cause this or what else could be the problem? please help