yeah shit just get a bottle of Meguires quick detail and spray and wipe after every ride and you'll be good. no need to ever wash the bike with water imo unless you get caught in some nasty rain or some how get nailed with mud...
on the main issue... yeah check to see that you didn't somehow dislodge a hose... also check that your fan is working... you may have unplugged the fan if there's a quick disconnect you hit with the high pressure water.
how long ago was this? does the bike overheat when it's idle'n or only at speed? does your fan come on... how is your coolant level?
when you washed did you try to avoid the motor with the pressure washer? or did you intentionally wash the motor? be honest... that pressure is a lot for hoses and wires...
good luck bro.