I'm not sure if you are looking for a cause or a cure?

today is Thurs. You last worked out on Tues, is that right,with soreness starting Wed afternoon?
What did you do either Mon or Tues - did you up weight on lifts or up reps/sets? If not your workout, Did you do anything unusual - like have to take the stairs at work or jog a hilly route? Move a couch? Anything that would have been weight bearing and stretching your hams/glutes at the same time - like carrying & putting down heavy boxes?

if it is just unusual DOMS (and not sciatica), I find that a light workout of same muscles is good - e.g. bodyweight squats. Seems to get the blood moving, as does alternating hot/cold in the shower. the "sore to touch" just takes time to abate - you're probably a little swollen/inflammed and the nerves are just irritable to touch.