Is it reliable enough or do i need a second opinion?

My last period was the end of Feb. - the beginning of March. I haven't had a period since and i've missed two since my cycle is 25 days. I took a dollar test where you pee in the cup then you use the plastic dropper to put the urine on the test. It came out positive. I'm not sure if the test is reliable enough. Should i buy a more expensive one or would i be wasting my money?