Frozen Cursor MacBook Pro 13" w upgrades

MacBook Pro late 2011 w cursor that yesterday became frozen or near-impossible to move. Upgraded 6 mos. ago by upgraded Mercuru memory & Mercuru SSD 487.87 GB. Until yesterday, started up & ran like a Swiss watch. Have tried reboot; command/option/P/R/power; removal & reinsertion of battery (also fairly new). Able to get to disk utility but cannot move cursor to First Aid. Any suggestions?