Brief Answer:
If you haven't had liver issues ever, there us no need to do liver chemistr

Detailed Answer:
Hello dear, welcome to Ask a doctor service.
I read your query and here is my advice.

You have been taking 2 extra strength Tylenol and the amount of acetaminophen they contain is 1000 mg. They have a half life of 1.5 to 3 hours which means that their concentration in blood is in half in three hours and are completely cleared out of system in 24 hours. I can't calculate the amount of alcohol because different drinks contain different amounts of alcohol. Also isotretinoin is a supplement that can affect liver.
I think if you are a person without a history of liver issues like hepatitis B or C, fatty liver,impaired liver function or altered liver chemistry recently, you may be at risk for toxic hepatitis.
Also if you develope any abdominal pain in upper right quadrant, nausea, vomiting and fatigue you may need to get tested.
If you have no symptoms, if you haven't had impaired liver function recently, if you haven't had a liver issue ever there is no need to do liver chemistry despite taking Tylenol, alcohol and isotretinoin.

Hope I have answered the question.
Let me know if I can assist you further.

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Brief Answer:
You may wait for 2 to 3 days for symptoms to develop.

Detailed Answer:
Hello dear and thank you for asking again.
The time of appearance of symptoms of liver toxicity may vary from days to weeks. This time varies according to the exposure you have.
I can advise you not to take more alcohol and take acetaminophen only if you are having fever.
The symptoms of the exposure you had may appear probably in 2 to 3 days and if you limit alcohol intake the risk gets low in next comming days.

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