In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
2- You did not try to work it out and you did not ask, so you have to repeat those prayers.
Answering your question, the Fatwa Center at Islam Q & A, states:
Facing the direction of the qiblah is one of the conditions of the prayer being valid. A slight deviation from that direction is overlooked. But a large deviation is not. Also, one who tries his best to work it out and gets it wrong is forgiven.
What appears to be the case from your question is that you did not try to work it out and you did not ask; rather you did not pay attention to the changes made in your room that caused this confusion, so you have to repeat those prayers.
If you cannot work out how many they were, then you should make up whatever you think most likely to be the number of prayers so that you will have discharged your obligation.
Almighty Allah knows best.