Should i be worried about his insect/spider bite?

ABSOLUTELY! It sounds like you may have a bad case of cellulitis. If untreated this condition can be very harmful to your health. You need to make an appointment as soon as you can with your family doctor so that you can get on the proper medication to fight off what ever infection you may have. Also, they may be able to determine if you have any allergies to what ever bit you. You can't be sure of what's going on until a doctor diagnosis and treats you. Hope this helps and hope you get to feeling better!

First of all if your entire arm is ever swelling on one side you should ALWAYS seek a doctor or medical help. I am no expert, but depending on where you live, it could be a spider bite. If you live in Australia or a part of Africa, then there is a good chance that a type of spider could have bitten you and caused this swelling. What kind of climate do you live in? What time of year is it there? Summer? Winter? Is it snake season, or do snakes live in the area you are in? A lot of it depends on where you are and what it's like right now, if you could elaborate more about your environment maybe we could help identify...

It definitely sounds as if you have had a reaction to some kind of bite. I would see your doctor as the swelling and pain seems to be a little extreme for a mild reaction. I doubt it is deadly, but the toxins may be working through your body slowly and will need to be halted. It may go away on its own, but it also might indicate that you could experience a much worse reaction if your are bitten again in the future and your doctor may advise that you carry an epi-pen just in case.

I would go see a doctor. You might be allergic, and the insect culprit may have been poisonous even if it isn't lethal... plus they might be able to give you something for the pain or to stop the swelling.

I'd suggest going to see the doctor. I can't really help you over the internet...

if it is worrying you, go see a doc. why wait? let your mind be put to ease.

huge swelling: definitly see a doctorb

No you should be fine, take some benedryl to help with the reaction you are having. If it persists for a couple more days I would go to the dr.

If it was anything really serious the skin around the bite would turn black and start to decay. I think you should be fine. I would keep an antibiotic cream on it though.