Spotting after 10 days of periods. Next?

I got my period as usual on june 22nd and then i got spotting june 6th.. thats mean after 10 days of pervious periods. Usually i get once in 25 days for 5 days. After that till now i didnt get periods. Pregnancy test taken. Negative result. thyroid and pelvis scan too done. 12.5 mg thyroid tablet were given. And small clear cyst of 3.5*3.0 cm found in Left overy.  In the second pelvis scan after a month it was found in right side. Doctor gave me tablet to induce periods. Taken for 5 days till last friday night. Still i didnt get my periods. I was asked to come for another pelvis scan on my second day of my periods. There are few questions. 1. In First pelvis scan doctor said cyst in left overy and in the second scan she said it was in right. How could that be happen?? Any possibility to shift from one side to another?? 2. Is this a major problem? 3. What could be the reason for my delayed period? And even didnt get after taking tablets to induce. 4.whats next?