Seeking advice...

A little history of allergies before I explain what happened: I have hayfever all year long, I'm allergic to dust, aerosol (not bad though), and spring is the most irritating season of all.

But I'm not so sure about bad reaction to bug bites. I remember I got stung by a bee about 9-10 years ago (I can't remember exactly anymore), and I remember that the itchiness from the sting stayed for months almost a year. About 5 years ago, I got an ant bite at my lower back (on the right of my waist) it hurt so much when it bit, it's probably about the same pain that I got when I got bitten by an ant when I was little. But the bite mark (I got a mark like a mosquito bite, very little though, and doesn't hurt, and not itchy), stays with me until now. It never gave me any problem, but I'm just wondering why it doesn't go away? And is there anything I should watch out for in the future?

Thanks.