I've started on 12 tab of prednisolone in 07/2011 as my sle is active. Now I'm taking 1 tab/day, but I'm having sleeping prob/mind thinks all the time?

Steroid mood swings. Steroid medications like Prednisolone can cause depression, mania, anxiety, and suicidal ideation. The mood changes are undpredictable; your mood appears to be getting higher. If you cannot sleep at least six hours or so, you might need to lower your dose, to avoid becoming manic. If you start gambling, shopping excessively, speaking rapidly, or arguing with everyone, see your doc asap.
Psychological. Steroids can cause many psychological problems that really need to be treated. It gets confusing because we generally think of psychological problems as being... "psychological, " not "medical." that is a false dichotomy. It probably would be useful to get a psychiatric consultation now because thinks can get worse quickly. You might not need treatment now, but, be prepared.