Hi, I Have Been Bitten By Something On My Calf

Hi, I have been bitten by something on my calf while moving the grass. It was a sharp pierce. Later a rash appeared around the bite. After a fl about a week it almost disappeared but then one morning it came back outside the initial tag area but about twice in size and in a U shape that morning I also had a headache which remained fur most the day. The rash looks like reddish bumpy skin. Please help. It is quite itchy.