i have a 93 k1500 blazer in silverado trim, at first my high beams just stopped working it shuts off my lows but doesnt turn on the highs and it doesnt show the indicator on the dash.. now when i cut on the lights it kills the truck if i rev it befor it drops the rpms a little bit any help!?

and on a side note when its in overdrive at low rpms i notice my tach jumps and so does the whole truck sometimes really hard untill i get the rpms up over say 2200 and it does it when i push it down in od at first

thanks for anyhelp