You already received. 2 descriptions of tick bites. Flea bites may be clustered into 3 itchy bumps that bleed ; blanch (turn white) when you press on them. They tend to be found at skin folds (breast or groin) ; folds of joints (ankle, knee, elbow, axilla) as well as legs. A rash ; swelling can occur as well as secondary infection from scratching. A skin biopsy is sometimes needed for accurate diagnosis.
Hard to say. All insect bites can cause a local reaction with redness, swelling, warmth and itch. If the red area is becoming like a bulls-eye, then see you doctor. To transmit disease tick generally need to be attached from 2-3 day or longer.
Hard to tell. Any insect bite can look fairly similar. If the tick is engorged (full of blood) and stuck to the skin, it is easy to identify. As for other biting insects (mosquitoes, gnats, etc), it may be hard to tell if you don't actually see the insect involved.