For a 27yrs man the symptoms are quite serious i think .
You need a thorough clinical check up and investigations to reach a proper diagnosis and effective treatment .
one thing is for sure that you are not having balanced diet and having nutritional deficiency
lead to ,weakness ,dulling of brain and all those .
Please see to it that you are not taking any medicines that make you drowsy .
Avoid excess drinks if at all you are taking .
you need regular physical exercises and healthy balanced diet to remain alert and active
Please get a consultation and the tests done for proper treatment .
Hope you be all right soon