Thank you for the additional information.
There are several conditions to consider in this situation.
The description of symptoms is most worrisome for environmental sensitivity, which can be an allergy, but when you are responding to a variety of odors, it is more typical for non-allergic disease, such as vasomotor disease. This will cause symptoms similar to allergies, but many different environmental stimuli can precipitate symptoms, including any strong odor or changes in environmental conditions, such as temperature or barometric pressure.
When someone has sudden worsening of allergic or non-allergic symptoms, the most common cause would be a viral infection, as the infection will increase the sensitivity.
There are several interventions that you can try at home to help with these symptoms. The primary interventions will be an oral antihistamine, such as Benadryl, although there are many others. An H2 blocker, such as ranitidine, may help with the respiratory and the abdominal symptoms. There is also now a steroid nasal spray available over the counter, Nasacort, that may work better than antihistamines for many people. It also would be important to perform general supportive care, such as getting plenty of rest and drinking plenty of fluids.
If these interventions ease the symptoms, then no further evaluation or treatment is necessary, but if the symptoms persist, then it would be appropriate to see your doctor.
If I can provide any additional information, please let me know.