Why was the house treated a month ago when the bites only began 2 weeks ago? Could this be a sensitivity reaction to the chemicals applied 4 weeks ago? Do a google image search for papular or follicular contact dermatitis. Of course those who get their photos in journals have the nastiest cases, but you will get the idea.
If these are bites, there should be a tiny hole or bite mark in the center of each "pimple" that may need a small bit of magnification to easily see. No see ums apparently
do NOT live inside the home so if you are sure these "bites" are from an indoor source you will have to find a different predator.
Taking a daily dose of a long acting "non-sedating" antihistamine may be a good thing to try, eg cetirizine.