Omnaris is an inhaled corticosteroid. Despite being a steroid, it is relatively benign, without adverse effects on other parts of your body. However it is not a medicine you would want to take indefinitely. You might want to ask your doctor if you could try the lowest dose and, if that is effective, if you might try using it every day. Or ask if you might alternate it with a nasal antihistamine.
More to the point however, would be to determine what is in your home that caused this problem in the first place. Indirect evidence that there is something in the home acting either as an allergen or an irritant, would be relief of symptoms while on vacation. You could be allergic to residual animal dander, insect debris, mold or any of a number of chemicals/cleansers you use in your home. You should ask the allergist for his/her best guess about what, in the home, you might be allergic to. You might also consider having your home surveyed by an industrial hygienist.
I am glad that you have gotten relief but the best approach to chronic symptoms, be they from allergens, infectious agents or chemicals, is separation from them or avoidance and, if you could find the cause, the expense of such a survey would be well worth it.
Good luck.