I am a liscensed estitichan (who can't spell...) as well as a makeup artist so I can give you a little friendly advice. First off, do consult a dermatologist, my advice is not to get you away from that just to help out until you can because I know around here it can be months before you get an appointment. Second, remember that with the heavier foundations (Studio Tech, Studio fix...) a normal cleanser is not enough to get your skin clear of all the residue. You really need a product like Cleanse Off Oil to get all traces off. I know with me I use my Studio Fix Fluid and I apply it to my hand then dip my foundation brush into that and put it on my face, well when I clean my hand off with my normal cleanser, I can see it's not getting it completely clear, so I knew I needed something extra, try this experiment at home to see how your cleanser is doing. Anyway, I do the Cleanse Off Oil then my normal Aveda cleanser which is gentle on me (not endorsing Aveda it's just what I use since that's who I work for, you are welcome to use what works for you).
If the cleanser isn't the issue, it could be your skin reacting to a new product. I go between MAC Studio Fix Fluid and Aveda's foundation and they have different ingrediants and I will have an initial breakout each time (usually cystic acne which is the deep bumpy red ones), then my skin gets used to it and I'm fine, it takes about 2-3 weeks. For those types of bumps the best things is a salicylic acid spot treatment which will help the red go down and shrink the size of the blemish. And please don't pick at it it truely does so much more harm than good! If you are getting the little white bumps, those are best treated with the spot treatment and a good gentle exfoliator since they are clogged pores.
If that isn't the problem then it could a sensitivity to an ingrediant, in which case you wouldn't have known until you tried it. Again I'm not a doctor but my professional opinion is that if it keeps happening after using it for 3 weeks, change to something else that has the coverage you want with a little lighter ingrediants.