How To Create A New bash_profile And Connect New Database To It In Oracle
First, remove all that junk from .bash_profile. Use oraenv. Example:

$ grep u01 /etc/oratab
MIN112:/u01/app/oracle/product/11.2.0/dbhome_1:N
MIN121:/u01/app/oracle/product/12.1.0/dbhome_1:N

$ . oraenv
ORACLE_SID = [oracle] ? MIN112
The Oracle base has been set to /u01/app/oracle
$ env | grep ORA | sort
ORACLE_BASE=/u01/app/oracle
ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1
ORACLE_SID=MIN112

$ . oraenv
ORACLE_SID = [MIN112] ? MIN121
The Oracle base remains unchanged with value /u01/app/oracle
$ env | grep ORA | sort
ORACLE_BASE=/u01/app/oracle
ORACLE_HOME=/u01/app/oracle/product/12.1.0/dbhome_1
ORACLE_SID=MIN121


Second, forget /u01/app/oracle/product/newdb.
Just run /u01/app/oracle/product/11.2.0/dbhome_1/bin/dbca and create your other database and provide the necesarry path for datafiles. You do not need another ORACLE_HOME for another database.

When you have multiple databases, just put them in /etc/oratab (dbca will do this automatically in 11.2), and use oraenv or just set ORACLE_SID in case of the same ORACLE_HOME for switching between them.