First real laugh and possible allergies?

Yesterday, I got Tristan to laugh or more like smile with a noise. It may have happened before but this time I was able to reproduce it for 5 minutes. It was fun to see but a lot of work for me and then he just lost interest altogether.  Laughing sure makes playing much more fun!

Yesterday, I also noticed what looked like a cold hive on Tristan's lower leg. That made me wonder if it's not too early for babies this young to have allergies. After doing a bit of research online, 2 months is not too young to get allergies.  I was really hoping he would not get my cold allergy :(  I didn't get my cold allergy until in my twenties or at least that was when I first noticed them. In the past couple of baths, I also noticed unusual dry patches on his belly.  I sure hope this is not eczema.  If it is, apparently it is quite common and may go away as stated in this Q&A on eczema.  He had a lot of goose bumps on his body when we removed him from the bath tub too. That's unusual too. We're wondering if he is somewhat sick since he has been extra cranky these days.  The hive on his leg could have been from his mild cold, if that's what he has.

I've read that breastfeeding an infant will lower his or her chances of developing allergies later on in life.  This is one of the reasons why I am so determined to keep up the breastfeeding.  However, there is nothing that can prevent allergies for sure as stated on BabyCenter.  One things I will try to do more now that I have read some of the articles online is to vacuum.  We are so terrible when it comes to vaccuming and cleaning the house.