MySQL --- MONTH(NOW()) AS m, DAYOFMONTH(NOW()) AS d

Hi, Everyone:

I want to do a MySQL date and time differences.

I had made a speperate table in regards to everytime a user logs in and out a datetime has been stored in the database.

This is the following MySQL script.

CREATE TABLE IF NOT EXISTS `usercounter` (
  `usercounterid` varchar(35) NOT NULL DEFAULT '',
  `userid` varchar(35) DEFAULT NULL,
  `firstlogindate` datetime DEFAULT NULL,
  `lastlogindate` datetime DEFAULT NULL,
  `ipaddress` varchar(15) DEFAULT NULL,
  `browseragent` varchar(150) DEFAULT NULL,
  PRIMARY KEY (`usercounterid`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

Now I want to see the difference between the two dates and times on "lastlogindate" and "firstlogindate".

Here is the MySQL script.

SELECT  usercounter.userid, usercounter.firstlogindate,  usercounter.lastlogindate, usercounter.ipaddress,  usercounter.browseragent, useracct.username, useracct.f_name,  useracct.l_name, useracct.dateofreg,
DATEDIFF(usercounter.lastlogindate,usercounter.firstlogindate) AS differenceInDays,
TIMEDIFF(usercounter.lastlogindate,usercounter.firstlogindate) AS differenceInTime,
FROM usercounter, useracct
WHERE useracct.userid = usercounter.userid
ORDER BY usercounter.firstlogindate DESC

What I want to do is the following using "differenceInDays" and "differenceInTime" is as follows

MONTH(differenceInDays) AS m,
DAYOFMONTH(differenceInDays) AS d,
HOUR(differenceInTime) AS h,
MINUTE(differenceInTime) AS m,
SECOND(differenceInTime) AS s

However, it only works with the NOW();

MONTH(NOW()) AS m,
DAYOFMONTH(NOW()) AS d,
HOUR(NOW()) AS h,
MINUTE(NOW()) AS m,
SECOND(NOW()) AS s

I want to see my MySQL script work but it doesn't so is there a way around this?

SELECT  usercounter.userid, usercounter.firstlogindate,   usercounter.lastlogindate, usercounter.ipaddress,   usercounter.browseragent, useracct.username, useracct.f_name,   useracct.l_name, useracct.dateofreg,
DATEDIFF(usercounter.lastlogindate,usercounter.firstlogindate) AS  differenceInDays, MONTH(differenceInDays) AS m,  DAYOFMONTH(differenceInDays) AS d,
TIMEDIFF(usercounter.lastlogindate,usercounter.firstlogindate) AS  differenceInTime, HOUR(differenceInTime) AS h, MINUTE(differenceInTime)  AS m, SECOND(differenceInTime) AS s
FROM usercounter, useracct
WHERE useracct.userid = usercounter.userid
ORDER BY usercounter.firstlogindate DESC

The above gives me an error.  Am I missing somethhing or is there a better way.

Thank you.