Different tests, different results?

Rebecca • M: 10/15/05 | 33yo | TTC#1 for 3+ yrs | 1st BFP: 10/4/16 | MC: 10/24/16 @ 6w2d | 2nd BFP: 8/19/17 | 2nd MC: MMC 9/20/17 @ 8w2d | 3rd BFP: 3/11/18 | 3rd MC: 3/31/18 @ 6w1d | 4th BFP: 1/30/19 and still going!! 💜🙏🏻🌈👶🏼 | Healthy baby girl born 9/20/19!!!

I just took a test this morning, which was a faint positive. I took another to confirm, and no line. They are different brands- could this mean different sensitivities in detecting hcg?