Suggest Remedies For Itchy, Red, Bug Bite Marks On Body

I am trying to identify the type of insect or bug that is biting me and what further measures I can take to stop it, get relief, etc. I have already sprayed my mattress and box spring with a substance said to kill bed bugs. I also put the mattress and box spring in encasements and washed my linens in hot water. Problem is that I do not see any of the things biting me. After taking these measures I am continuing to get new bites. Looking online, it appears that I may be getting bit by mites (scabies), fleas, or chiggers. My bites are on my inner thighs, butt, one foot and upper arms. Any ideas about what sort of critters these are and what medications and/or other measures I can take to put an end to this. My major symptom, besides the red bites themselves is terrible itching.