Can allergies lead to a sinus infection and then to bronchitis? my temp hasn't gone greater than 98 but been feeling really bad.

Rather infection : Viral infection can cause the symptoms described, can start in upper airways and affect lower airways too. Allergy is a sort of chronic inflammation, which can flare up by a virus or other triggers, but viral infection is the most common, and yes you can have a low grade temperature too. So, rest , fluids, painkillers, saline nasal washes would help, if not see your doctor, wish you wellness