Had headlights, then high beam only, now nothing

Also, where is the headlight relay & what does it look like?
{Reminders, if it will help: With the old headlight switch, no headlights
With the new switch, got high beam
Try low beam, & it's like a dead short & pulls car's amp
meter, strongly, to discharge!
and the back end of the light switch gets very warm &
close to being hot.

Still checking things out, by the way. just need whatever info or thoughts, you all might have, that could help me get this done. Much appreciated.