Have you used a bacteria supplement - Safe start etc..?
If so, sometimes you miss the nitrite spike as the bacteria that converts it is in abundance in these bacterial additives and you see a nitrate spike first
If not test your source water for nitrates, could be that the 5ppm that your seeing is from your source water and your at the start of the cycle.
Either way, you may miss the nitrite spike
Let it run for a few more days and measure ammonia, if it’s decreasing and nitrates increasing then your on the way!
Best way to test shorter term is ignore the nitrate and concentrate on ammonia, that logically has to reduce to produce the other 2 bacteria - when ammonia drops from 0.5ppm to 0.25 then test for nitrite/nitrate. Stops some frustration and wasted tests
Out of interest, what did you dose ammonia to when you started and with what, and how long ago