how often do you throw up straight stomach acid

Yeah I'ma nurse and @isern-i-phail is right, add like 1/2 or 1/4 tsp to half a glass of warm water so it readily dissolves.

Otherwise you can try taking one or two Benadryl/diphenhydramine (the allergy medicine) and that's also an effective anti-emetic/anti-nausea. It might sound weird but a lot of anti-nausea meds work by blocking histamine which plays a large part in nausea/vomiting, and benedryl is actually used as a control for testing new anti-nausea drugs because it's still quite effective. You can also let it dissolve under your tongue and it will still absorb (but it will taste terrible/bitter), useful though in case you can't keep anything down. Alternatively you can try getting it a little wet and boofing it lol.

You might try calling your docs office to see if they'll write you a script for promethazine or (even better zofran.) A lot of them will do it without an appointment if you just ask them directly for the med and tell them you've safely taken it before.