Anxiety. Please advice someone??

Anyone with anxiety, what do you do when you feel it creeping up for no real reason? I've never been diagnosed but I know I have it. Awhile back I had some stuff going on that had me scared and anxious almost constantly. It's been taken care of since but today I thought about it and now I'm fighting the urge to freak out and cry. The situation I'm referring to could possibly cause some problems if it comes up but it hasn't so I don't know what is wrong with me. I just can't get it out of my head and I feel an anxiety attack coming. I want to cry and vomit and hide somehwere. Someone please give me some advice on what I should do? I'm a SAHM and I babysit so leaving to see a doctor is not an option at the moment. I need something I can do right now to help. Also I'm the kind of person that thinks because I'm thinking of something that means it's because it's about to come up and cause problems if that makes sense. Like I think since it's on my mind it's like a premonition that it's about to happen. That adds to the anxiety.