What I can do if I´m not sure that we broke up

Hello Kevin,
I´m 23 years old and my boyfriend is 30 years old. We met us three months ago and we have beening together as a couple for two months. Before I met my boyfriend, I was applying for a semster abroad. I recieved a place and he supported me and told me that he will wait for me. I have beening in the new country for almost one month and everything between us was perfect. Actually, I was missing him so much and because of that I was writing him a lot of messages. My boyfriend has his own business and last week he told me that his business partner is on holiday and he is very stressed. I didn´t get exactly what he means and I was writing him constantly,but he didn´t reply or he answered with one sentence. One night I wrote him that he doesn´t diserve a girl like me and we argued. I knew that I was guilty and I tried to fix it. I apologised to him and I told him that I wasn´t right, but he told me that he wants that I am happy and for me will be better to find someone else. I was shocked, when he wrote me that he should break up with me. I started sending him longer and longer messages, voice messages, in which I was crying and telling him that I love him. At the end he told me that we can speak each other, because I was begging him to explain me why he wants to give me up. He is not this kind of people, who gives up so quickly. When he called me, he told me that it is not fair for me, because he can not give me the attention, which I need, because of his job and he doesn´t know how long this will continue. I told him that this is a difficult situation and it will not continue forever and I can wait, but he sounds so miserable. I could not believe that I spoke to the man, who I know. I asked him if he was honest, when he told me that he likes me very much and that I will be his last woman and he answered, YES. So, I aksed him if we are still together and he told me: I don´t know!. After that I asked him if I can write him and he told me that I can write, but he doesn´t know if he will reply. I really love this man. He is my first man and he is my dream man. I don´t want to give up, because I have the feeling that he doesn´t know what he really wants. I don´t know if we are together or not. I sent to him two postcards, but I think that he deosn´t recieve them yet. My question is: Should I stopp writing him or should write him and show him that I support him and I will not let him when he has difficulties? I am sorry for my English, but this is not my mother language.