Advice please?!??!!

Okay so this is over Pinterest before I start. I messaged this guy that was following me and told him if he still wanted to follow me that I had a new account and that that one wasn’t working right, he said alright and then said we should be friends, I said “idk” and now he’s texting me . I asked him his age he’s 23 and I told him I’m 13 he was like can we still be friends and said idk again. Now he’s being “ friendly” but kinda seems flirty . My guts telling me to stop but idk I would feel bad