I seem to be having some problems wif my ps3 slim. Just right after 15months

The thing is it takes some time before it can detect my disc when i turn it on and insert my disc. Then it keeps making dis ejecting sound (the sound when the disc eject... mechanical sound of the disc tray i think) but the disc doesn't eject. But after running for awhile then it becomes fine. Even if i insert another game it doesnt make any mechanical ejecting sound of the disc and the console detects the disc quickly as well. Its only if its the first time running after many hours turned off then it happens.

I hope my explaination isn't too confusing. Anyone know wats the problem? Should i bring it bac to the game shop and check it?