Digital pregnancy tests?

For those who are pregnant. Are the digital tests often not sensitive? I’m 15dpo and almost 2 days late for AF. She doesn’t feel like she is on her way?? But feel sick and nauseous and dizzy now for a week. Had a faint pos yesterday on a cheap pink test but worried it was an evap as a digi said no. I have read digi are not that sensitive at all? I’ve ordered some dirt cheap ultra pink dye sensitive ones from the Internet as don’t wanna waste more money