How bad is this?

lately i'v e been kinda forgetful. Like ill be watching a show for like 20 mins and ill be really into it and then turn it away for a few minutes.. and then try to go back and i can't remember what i was watching! Thats been happening alot. Or just now i can't remember the name of this kid that i've hung out with a few times this month.. what is going on? I'm an 18 year old female.