Can't lose him to irrational doubts, please help

okay things took a bad turn with my boyfriend, after putting myself in a really bad mindset because of googling my feelings it added to my doubts. i am very young and he is my first boyfriend therefore people were saying that it will never and should never last etc, i need to be alone to figure out what i want and the doubts will never go away. this upset me so much and i honestly couldn't stop thinking g about it to the point where i believed it. this is ruining me, i love his so much and know if these doubts disappear and my overall mood was increased we could be very happy. I told him my doubts again last night as they became to seem so real and i couldnt help but cry, he left me saying i need to think of what i want and let him know, he'l undertsnad because he loves me etc. I cried all night and could not sleep, i do not want to give up i really dont i want to be with him, i know i am young but im not interested in other experiences with other people so why are these thoughts circuling me? i cant live without hi,=m he is actually my everything, we have grown up together and i love that, i love how our relationship was but my doubts have taken it over. i know i dont want to break up and im going to propose taking i9t slow to him? so i can work on myself at the same time, get me out of this deperssion and hopefully have a clear mindset. what do you think? i dont want this to end i really dont!