line test has a faint positive digital says negative 😒

Sarah
Confused - I've had faint positives on line tests since 10dpo. Now at 12 dpo I had a line pop up within 1 minute. Used the same sample and did a clearblue digital. Says not pregnant. I looked over the box to see if it had the sensitivity on either but couldn't find it. 
Anyone have this happen and wind up pregnant or should I expect a chemical?  Photo taken at a minute + 30 seconds. Thanks!Â