Does my boyfriend really like me, can he change or am I being taken for granted?

My boyfriend left on a 2 week trip. He called two days after he got there and then called 2 days later and texted me during the weekend saying he missed me. However, it had already been 5 days since Ive spoken to him and I did not feel that the text was sufficient. We have only been together for 4 months and cannot understand why he couldnt just pick up the phone to call. He also had no explanation for it but said that he misses me and talks about me to his friends. I dont understand the logic behind this behavior. I exploded on him explaining that he was selfish and inconsiderate. Am I being taking for granted?