Hey!

I’m sorry for not getting to this earlier but I figure I can try and help out for future reference. 

The big question here is- is this type of soreness you are experiencing common when you train legs, or train in general? If you are training and getting “excruciating pain” 4-5 days later and this is a common experience, then I would suggest evaluating your diet. Provided you are not doing some style of training that is new to you and your training is within “normal” boundaries then your body should be recovering quicker, generally speaking. 

Are you consuming a recovery shake post workout? If not, consider a shake that will yield some fast acting carbs and protein. Additionally, make sure your calories throughout the day are sufficient. A diet that does not yield enough calories throughout the day is a quick way to excessive soreness. 

If you simply feel you went above and beyond what you normally do and you are now paying the price for it then making use of a foam roller and some stretching sessions can really help out. Despite what some might claim, a session with a little bit of lagging soreness will not kill you. Pay attention to what your body is telling and go from there. If you need to take a week off before hitting legs again then by all means do so.