Welcome to ECF. I'm sorry you're struggling right now.
My advice, for what little it's worth, is to avoid nicotine in all forms right now because of the vasoconstriction / vasodilation (apparently, it can do both) effects. If you think a replacement for the hand-to-mouth habit would help, you can try a nicotine-free vape.
Once the clot is resolved and things have stabilized, then it might be time to look at whether vaping with nicotine is something you want to consider. We don't have a lot of hard data on the health effects of vaping. What we can say is:
- Smoking is very unhealthy, especially due to the products of combustion (smoke, tar, ash, carbon monoxide etc.)
- Vaping has unanswered questions, but as it doesn't involve combustion at least the tar, ash and CO are not present. The indications are that vaping is (much) less harmful than smoking, although we can't quantify how much at this point.
Naturally, it's best not to smoke or vape. Full points to you if you can manage it. That said, the abstinence option didn't really work out for most of us here. If it's a choice between smoking or vaping, vaping's clearly the better bet.