Changing SQL Account and Password

Hello, about 3 weeks ago I went about changing the service startup account and password for the 2 SQL Service Accounts (MSSQL & SQLAgent) using the Service applet instead of the Enterprise Manager. I made a mistake in that I forgot to ensure 2 rights (Replace a Process Level Token & Lock Pages in Memory) when I made the change but the services were still able to startup and they ran for about 1 week. I have since changed the service startup account the proper way by dropping the account and adding it again via Enterprise Manager. I checked and all the rights, etc. that Microsoft requires are there. Lately our SQL 2000 Cluster has been acting up during peak periods (the CPU goes to 100%) and our site stops responding. This did not happen that much prior to this change. My question is: is there anyway what I did initially could've caused damage to my SQL cluster? Any way to fix it? thanks for any help.i don't think cpu spiking is directly (or indirectly) related to changes you made.