how do you know if it is over?

context: i have been in a relationship for almost 4 months now, i got with him a few weeks after leaving a 10 month relationship (ended badly, but i got over quickly). before we dated, me and my bf were very good friends, i would tell him everything.

the first two months were great, they were the best i have ever had, i felt loved. but now, almost everything about him annoys me. he will speak to me with a rude tone (he doesn't mean to) and i will crash out. he will make a smart ass remark and try to tell me i am wrong for thinking a certain way and i get annoyed. we never get into big fights, it is always little arguments, but i hate how mad i have been getting around him lately, it isn't fair to him. however, a part of me still loves him, because i care about him a lot, but i have confused on whether i love him in a romantic or friend way because i still worry about him and i still get somewhat happy when i see him or when he comes over. and i still get jealous when i hear about him talking to other girls, like his ex. i am confused and would love some opinions. 

how do i know if it is over? how do i know if i love him as a friend or romantically? i don't want to keep him going for someone who is unsure.