Question about testing

I had an unprotected encounter with a female about 5 months ago. I went to the doctor because i thought i had an std but it was just some irritation. For about 5 weeks after i was scared to death of getting HIV. I went to the doctor and he did a test which was 5 weeks after the encounter. I know that there is a window period but i also read that most are detectable by 4 weeks. Anyways, I went to the doctor for a checkup because he wanted to see if i developed any symptoms months after. It was about 4 months later. Is it okay that he did not have me take another test?? Those tests are expensive but should i trust the doctor that i didnt need another one?