He's never had another girlfriend than me. but i have how do i tell him theres more to it than just .?

theres this guy ive knows since about 6th grade and im a junior now. but weve dated on and off ever since. now were together again and its better than ever. well last night we went to the movies and we were the only ones in the theatre and he had his arm around me and he was playin wiht my pocket and i love what then my hand was kinda on his lap and he was holdin my hand and it was really sweet ya know. i wasthinkin aww this is perfect then he kinda started movin my hand on his... ya know and i was like omg because weve only been together this time about 2 weeks. but i went along ya know and then he started tryin to put my hands down his pants and itz not like ive never done anything before but i was scared to death for somereason and i jerked my hand back. then a few minutes later he tried to put his hand down mine and i said stop and he said sorry, then not even a minute later he tried it again! and i said stop and he said sorry again. how do i tell him that rushin will ruin things?