Yes, allergies cause more issues than people think. Low histamine diet has helped me.

New carpet, old dirty carpet, bedding, wall hangings, if you have baseboard.. the heating elements need to be vacuumed out. If you have carpet, a used dryer sheet will pick stuff up under there.

Even if you haven't changed detergents, deodorant, shampoo, etc, you can actually develop a sensitivity over time. Im doubtful it's that for many people all at once though.