First response tests vs health department

Jade
Okay.. I took two first response tests today and within seconds there was INSTANTLY a faint line on them ❣ I went to the health dept and their test was negative??? Please help. What do y'all think. The nurse said she feels like I am definitely pregnant considering how fast the lines came up on the first responses and that she would def trust the first response bc of how cheap the health department ones are. according to tracking I should be around 4 weeks 2 days. My period is 3 days late. Has anyone experienced a negative health dept test before after two positive FR tests??