1
What you want is done by
Graphics[Table[Circle[{a, 1}, 1], {a, 1, 2}]~Append~Text["It's finished", {0, 0}]]
Here's another approach, with minimal changes to your code:
Graphics[
{
a = 1;
Label[tag];
If[a < 3, {Sow@Circle[{a, 1}, 1], a = a + 1;
Goto[tag];}, {Sow@Tex...