Hi, I'd like to help you with your question.
It sounds like you need to see your doctor for a full check up. Although I think it most likely is anxiety, it never hurts to be sure. And you cannot be treated for anxiety if the question remains about your physical health.
Once you have been cleared by the doctor, you should see a therapist for an evaluation. There are some possible scenarios:
One, you had an anxiety attack. The symptoms you describe sound very much like an anxiety attack. It could be a one time deal (maybe too much stress?) or the beginnings of anxiety an anxiety disorder, but either way, you need to have it checked out.
Two, you are experiencing a physical reaction to your withdrawal from alcohol and nicotine. Sometimes, because of the nature of withdrawal, you can have odd symptoms as your body becomes used to being without the drugs. Your doctor should be able to help you determine if you are experiencing this as a result of your sobriety.
Three, it could be the anemia. It may be that you need to take the supplements more often or need an increase in the dosage of the supplements.
It may very well be that you are stressed physically and are just experiencing a time of adjustment to all the changes you have made in your life. If you see your doctor then a therapist, that will give you the answers you need. In the meanwhile, try to keep yourself calm. This happened to you recently, so whatever it might be, you are catching it early so that is a good thing. Practice taking deep breaths, stretch, relax your muscles and/or do something fun to help yourself from focusing on how you feel. You will soon have the answers you need and that will make you feel more in control and better able to cope.
I hope this has helped you,