Really frustrated by MySql on start up server - mysql

Question

I've been trying to figure out this problem for like two days straight, please help.
I'm relatively a noobie, so please bear with me...
I installed MySql, latest version, using the dumbest way, i.e. dmg file, and also workbench from MySql site.
For the very first time, I used system preference to start the server, everything worked out fine. Then, I tried to create the sample database by using the sample scheme and insert statement files from MySql site. But when I tried to execute those two files, I was prompted for entering password, I had no idea what's going on at that moment, so I closed everything, Googled about how to set up my own password for the root user account for MySql, and used mysqldadmin setpassword... something like that to reset the root password.
Then, the nightmare starts... Since then, no matter which method I tried to use to start up the server, no luck, i.e. system preference, manually. (I do have the PATH environment variable set up correctly btw).
So, here're the two errors I'm getting,
if I just use sudo mysqld:
2015-02-10 20:45:58 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-02-10 20:45:58 49381 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/mysql-5.6.23-osx10.8-x86_64/data/ is case insensitive
2015-02-10 20:45:58 49381 [ERROR] Fatal error: Please read "Security" section of the manual to find out how to run mysqld as root!
2015-02-10 20:45:58 49381 [ERROR] Aborting
2015-02-10 20:45:58 49381 [Note] Binlog end
2015-02-10 20:45:58 49381 [Note] mysqld: Shutdown complete
if I tried this sudo mysqld -u root -p mypassword:
2015-02-10 20:10:22 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-02-10 20:10:22 48437 [Warning] Setting lower_case_table_names=2 because file system for /usr/local/mysql-5.6.23-osx10.8-x86_64/data/ is case insensitive
2015-02-10 20:10:22 48437 [Note] Plugin 'FEDERATED' is disabled.
2015-02-10 20:10:22 48437 [Note] InnoDB: Using atomics to ref count buffer pool pages
2015-02-10 20:10:22 48437 [Note] InnoDB: The InnoDB memory heap is disabled
2015-02-10 20:10:22 48437 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2015-02-10 20:10:22 48437 [Note] InnoDB: Memory barrier is not used
2015-02-10 20:10:22 48437 [Note] InnoDB: Compressed tables use zlib 1.2.3
2015-02-10 20:10:22 48437 [Note] InnoDB: Using CPU crc32 instructions
2015-02-10 20:10:22 48437 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2015-02-10 20:10:22 48437 [Note] InnoDB: Completed initialization of buffer pool
2015-02-10 20:10:22 48437 [ERROR] InnoDB: Unable to lock ./ibdata1, error: 35
2015-02-10 20:10:22 48437 [Note] InnoDB: Check that you do not already have another mysqld process using the same InnoDB data or log files.
2015-02-10 20:10:22 48437 [Note] InnoDB: Retrying to lock the first data file
I try to make some config change in my.cnf file, but I can't even find it under my /etc/ directory...
Any help would be extremely appreciated, I'm really starting to hate myself... T.T
p.s. when I tried using mysqld-safe, it looks like the server has been started, but in the workbench, it clearly says the server is still stopped...