Advice needed, by experienced women!!!

Hi my name is Allie I am 17 years old and am dating an older guy. As you can probably guess I am sexually active with him, and I am worried that I could be pregnant. We use the "pull out method" due to him being allergic to latex. He is very good about pulling out and I am not worried about the actual ejaculation but the pre-ejaculation is what makes me worried. K so here is the situation, last month I was on my cycle and we choose to have intercourse, he pulled out and everything went fine. The next day my cycle totally stopped, about a week later I started to spot, it wasn't enough to need to wear anything and it kind of came and went from day to day. But now I often feel sick and tired, here are some of my symptoms: fatigue- i go to high school and the moment I get home I crash and sleep until dinner, Nausea- I have yet to acutally vomit but often just have stomach aches, Headaches- there is not a day that goes by that I don't have a headache, Temp- often times i feel super hot, Dizziness- when ever I stand up I am dizzy and feel nauseous. All of the people in my household are on their cycles as we speak meaning I should be also, but I am often times late. I don't really know symptoms of pregnancy and these are just some of the things I am feeling. Do you think I am pregnant? I know there is no way to know until I am tested but do to me being living alone and parentless, money is tight and I need to have some opinions on if it would be worth my while to go get tested or whether I should wait. Please get back to me as soon as you can I greatly appreciate it.