"Shall I go?" vs "Should I go?" Is my interpretation below correct?
Shall I go? Means that I am determined/poised to go and ask for your affirmation.

Should I go? It means I want your suggestion.

Question

"Shall I go?"  vs "Should I go?" Is my interpretation below correct?
Shall I go?  Means that I am determined/poised to go and ask for your affirmation.

Should I go? It means I want your suggestion.

Answer

Yes. It is more clear using "we."
Suppose you and I are at a party together. 
1. I am bored and want to leave. So, I say, "Shall we go," meaning "i want to leave if you don't object."
2. We need to be somewhere in an hour, and there might be traffic. I say, "Should we go now, or do you think we can leave in 20 minutes and still get to our appointment on time?"

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