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You're doing all the right things, and it sounds like you've got a very good attitude - both will help him. He may not show it to you, but the level-headedness you show him models hope - and trust me - that really matters.
There are online therapy sites. Live Person is a reputable one to try. You said you found an online CBT class....here is a link to a self-help site that is very well researched. Link
It's quick and to the point, as well as accurate. Another great site is worrywise...it's meant for kids, but they really have great stuff in it, and explain anxiety well. Worrywise
There are online medical consultation sites like Easy Health
. You can explore them, but make sure to ask if they provide prescription services for anxiety before you pay. It sounds like your son needs anti-anxiety medication, and there are quite a few rules about prescribing those - depending on where you live. To look for more, google "online medical consultation"....that will get you to the sites you're looking for.
My best to you and your son.
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