Social anxiety can be very debilitating in many areas of life and not just swinging although lifestyle is very much a social setting as well as a sexual one and the value of common social skills can not be overstressed. Social anxiety can be treated and many social skills are in fact just like any other skill and they can be learned and improved. that might be something you may want to look into.
However I am definately not trying to make you feel like you have any problems or need a shrink or anything but you did sound like this may not be the only area in your life that is affected by your fears.
I'll give you some sage advice that Forest Gump would give you if he were here - Take care of your feet. (ok technically that was Lt Dan but work with me here)
Keep your feet in good shape and wear shoes that you can walk in. If your feet are in good shape and you have on shoes that you can walk in, then no matter how bad anything gets......you can just walk away.
I'm not trying to be a smart@$$ here, really. Think about it, if you have your eyes open, if you aren't skunk drunk or drugged so you have a clear mind and can make rational decisions. If you have shoes that you can walk in and your feet are in good shape, how much trouble can you really get in???
The real issue I think you are having is a confidence issue. When you walk in to any kind of "new" experience and in this case it's a swinging experience, you need to have confidence in the following things
- that you will be physically safe.
- that your husband will be there for you and will be compassionate and responsive to your needs, fears and desires.
- that your relationship will remain safe and intact.
- that you will be emotionally and psychologically safe ( ie that you won't make a fool of yourself or offend or harm anyone else and that you will not be emotionally harmed by others)
So no matter what you are doing, just ask yourself these questions - Am I in any danger? Is my partner supporting me? Is this causing any threat to our relationship? Am I at any risk of causing myself or others any emotional harm?
If the answer to any of those is a legitimate yes then stop and evaluate it and correct it (walk away if you have to)
And if the answer is no then ask yourself is there any kind of real threat or just anxiety. If there is no real threat then take another step forward.
You have three directions - forward, standing and backwards. Stay sober and be aware of your surroundings, if you encounter an actual threat then stop or step back. If no real threat take another step forward.
either way all three of those actions require healthy feet and good shoes.