your pickup's output might be very low, which may not be a problem at all. don't compare your singlecoil output to a humbucker output of other guitars (i'm assuming your strat has 3 singlecoils). Coz the singlecoils will always have a lower output than fullsized humbuckers (unless you're toking about stacked/mini humbuckers). Also, different within each category (if you have a humbucker), there are different outputs of the pickups. Some vintage pickups (Gibson Classic 57', SD Seth Lovers, Pearly Gates) cannot have the same output as other higher output humbuckers like SD Invader, Dimarzio ToneZone, Air Norton etc etc. Its not a problem, you'd probably need more amp volume to attain the same volume as another guitar. This, again assuming you have a S/S/S combination in your strat.
Btw, I love my Fender 57' Strat, low output vintage pickup!