Assalamu alaikom, inshaALLAH you will do well in your exams. Trust on ALLAH and inshaALLAH HE will not let you down. Here's something that might help. It's a dua for memory. INNEE AS-ALUKA YAA MUD'AKKIRAL KHAYRI WA FAA-ILAHOO WAL AAMIRA BIHEE AN TUS'ALLIYA A'LAA MUH'AMMADIN WA AALI MUH'AMMADIN WA TUD'AKKIRANEE MAA ANSAANEEHISH SHAYT'AAN. I usually put my right hand on my forehead and recite this dua. It actually works!! Hope you do well in your exams inshaALLAH. Wasalam