Latelly i've past 3 full days on the pc. for the past 4 days almost without using pc. i'm feeling excessive muscle tension on the side of head, tiredness, lack of focus that doesn't go away, what is?

Can be tension,,,: This can easily be tension or a tension headache. It can be easily from your work on the PC ( i assume it means personal computer), it can be from grinding your teeth if you do it, or it can be another kind of headache like a cluster or migraine from a miriam's of reasons, like too much screen light exposure. Less intense work, more rest, and a visit to your dr. For meds if it doesn't go away.

PC Withdrawal: Symptoms? Or related to stress, anxiety, sleep deprivation, add etc. See your dr for a thorough exam. Take care!