Your daughter is suffering teen pangs plus hormonal changes plus stresses of various sorts any & all of which can make other problems worse as well as creating problems. I know you said this started at age 9 but it may well have started before then without anyone realizing. Kids often ignore signs that adults would pay attention to.
Light sensitivity can be indicative of many things (eye problems, migraines - these come in many different forms - allergic reactions) the tingly skin & sensitive skin can again be allergy related or stress (or both) the feelings of illness, dizziness & retching from certain smells again make me think migraine or allergy.
A couple of problems with the therapy would be a) probably she was too young for it to work & b) if these symptoms are due to allergy, migraine, stress or hormones or any combination of these then she needs to be treated for the cause not the result. Being 16 these things may get worse before getting better due to her hormones etc as a teenager.
I could never wear sunglasses until I was well into my 40's as they gave me a headache & a hat still does, my daughter & I both react strongly(violently even) to certain smells & I am very light sensitive - which made the sunglasses issue a real problem!!
Sit down with your daughter & compile a list of the smells (or types of smells) that make her retch or even just turn her stomach (see if there are any common bases in them - for my daughter anything remotely petroleum based!! Not good). Go with the flow (that is don't stress her!!) when it comes to clothing - just let her wear lose stuff & try to keep rooms not too bright also try & keep her out of strong sunlight.
Counsellors/psychs etc can be good but they can also be an unmitigated disaster & very judgemental (i was one so I know!! - counsellor but I hope not too judgemental!!)especially of teenagers - having experienced first hand, through my daughter & as a counsellor I would be very very very very dam@n careful about taking your daughter for therapy of that type until you (not a dr or "professional" but you!!) have researched everything that might cause this sort of problem. Go to a search engine (yahoo or google) & type in causes of sensory sensitivity, or causes of sensitivity to light, causes of sensitivity to smell etc. Just to start.
Another possible way to go would be alternative medicine - homeopathy, naturopathy etc.
