Allergic reaction??? HELP

[MGEmum]

Hi My DS who is nearly 3 got bitten by something on Sunday night, did not realise until MOnday when he started to develop a rash around the site of the bite (hard and dark red). This got worse as the day went on so I took him to the doctor who suggested that I give him an antihistamine - this I did and the rash has gradually gone down.
HOWEVER, he is developing large lumps, look like a mosquito bite but WAY bigger and have a hot red edge to them... any ideas what these could be. He got them last night (they subsided) and then he got them again this evening on his arms, legs and tummy. I do not think they can all be bites as he was wearing clothes and I had covered him in a sheet to try and avoid him getting bitten.
Need some advice as it is really worrying me
Any help would be great.

[mum1986]

that sounds like either an allergic reaction to the bite, if it were me i would take him back to the hospital. better safe than sorry.
good luck and let us know how he goes.

[MGEmum]

Hi thanks for the reply - we did take him to the hospital because the lumps went down to be replaced by another type of rash - he deeloped a nasty cough and had the cold sweats!!
They said it was just hives (an allergic reaction to whatever had bitten him) - they also said not to worry too much as these lumps were likely to disappear and reappear somewhere else and that they might continue for a few days - but thankfully they are now gone...just the cold to deal with now - have had a few slepless nights as DS is coughing til he vomits..breaks your heart when you see him sitting up and pulling a metal bowl in front of him when he coughs in case he is sick and he is only 3