Can't Start in recovery mode

[AlfreG]

A few days ago I got the S3 Mini with the stock rom (4.1.2), so i downloaded odin in order to install CWM so i can change the ROM, i used the CWM 6.0.2.8 tar in odin 3.07 file and everything finished ok, but when i press the keys combination (volume up+home+power button) nothing happens. the phone starts normally, should i say that this is not the first time I install CWM in a phone (i did't before in alcatel and others but never in this one) please help me!!