I let myself down

I got back two of my test paper already . Non of them satifies me , unfortunately . For chemistry , I score 38 out of 40 . It may sound good to many people , but I did aim 39 . I was down by just a little bit , but still I'm off target , I'm not ok with it . As for Physics paper , I score 30.5 out of 40 . This is more disasterous . I was expecting like 33 or 34 . But then , who is to blame , or what ? It's me myself , maybe I didn't work hard enough to deserves the mark I aimed . Now , knowing my performance on both of this subjects , I doubt that my Econs is going to be better . Computer Studies paper will be tested on this Saturday and I'm not even halfway through my revision yet . Somehow , I just lost my momentum . I'm really down now .