It very well could be the peanut/peanut butter, or it could be the pollen, seasonal allergies and that sort of thing. I know as I age my allergies in general just keep getting worse. I seem to develop a new symptom every few years. So, it could be that. Right now I am miserable because of my allergies. Mold and Pollen are horrible, especially with the wind blowing it around for the last couple of days. Now that it is raining it is the pressure in the sinuses.
I smoked in the past, but it was purely a social smoking thing. I did smoke a little more at various times during my early twenties, usually a particularly stressful semester at school. But it wasn't enough to take control of me, because whenever I decided that was enough, I could stop. I haven't had one in years now.
My parents both smoked when I was a toddler. Apparently, my dad thought my mom had quit when I was born, but she was still smoking in the bathroom and flushing the cig butt down the toilet. I caught her smoking one and was just at that age where I would talk about whatever I saw. She was afraid that I would say something around my dad and she quit cold turkey. My dad still smokes. But has cut down alot since I had my daughter (the first few months we stayed with them). He doesn't smoke in the house at all now. He tries at least once a year to quit. In fact, he is trying again now. I am sure that being around the S. hand smoke so much of my life is the reason, I am like this. My other sister just had to go on an inhaler recently because she is prone to bronchitis. She is in her mid-thirties.
This is something that can just be building up over time. Get in to your doctor and get referred to a specialist to combat it. Good Luck!