Probably normal. Allergic reactions to insects most commonly occur with stinging insects like bees, wasps and fire ants. Local reactions to other insects are generally not allergic. Allergic reactions usually cause symptoms away from the bite. So, bitten on the toe and toe swells= not allergic. Bitten on the toe and lip swells= allergic.
Depends on symptoms. Normal is small, raised, itchy that is trasient. Large local reactions acn involve a whole extremity. Systemic (serious) reactions involve hives, angioedema (swelling), shortness of breath, nausea/vomiting and in some cases sudden loss of consciousness due to hypotensiion 9low blood pressure).