What is the right question to ask?

Recently I am extremely busy with my thesis (which seems to take forever to finish).

I joined a discussion group on the field I am researching and asked several questions.

For the first time, my questions were answered by my supervisor. (Question like 1+1)

Then, the second time, my questions were answered with another question. (Question like 1+1-1)

Well, the questions I asked might seem so simple to the group but to me, it's tough enough to make me sleepless.

I wondered whether the group will think or would have thought that I am so stupid as not to understand a thing in the thing I am researching.

So, what should I ask if not the things I don't understand? Who is the stupidest? The person who asks questions he/she doesn't understand or the person who keeps quiet on the thing he/she doesn't understand?