HCG isn't a surge. I've had positive digitals with a beta of 8 so I'd say it's really rare to have detectable amounts of HCG and not get a positive test.
99 percent of people will get a positive result by 18 days past ovulation, which is about 4.5 weeks pregnant. It would be really rare to be further along than that and still get a negative.
So technically you could be 14dpo and still have a chance that the test isn't catching the hcg in your system. It doesn't surge though like pp stated. Hope that helps!
BFP #2 2/3/14 | EDD 10/16/14 First U/S 2/10 Possible TWINS! | Second U/S 2/24 TRIPLETS!!!
Re: HCG
***SIGGY/TICKER WARNING***
TTC since September 2012 ~ DH(32): Non-obstructive azoospermia, Me(32): Normal
10/13 - TESE found sperm!! ~ 11/13 - IVF w/ ICSI #1 ~ ER 11/23/13 ~ 10 R, 9 M, 8 F
ET 11/29/13 ~ Transferred 2 beautiful hatching blasts, 5 frosties
12/5/13 - BFP!!! Beta #1 (12/7/13) - 189 Beta #2 (12/9/13) - 401 Beta #3 5871
12/16/13 U/S #1 - TWINS!! EDD - August 16, 2014 ~ 7/19/14 - Our beautiful baby girls joined the world!
HPT accuracy DPO
10 dpo : 35%
11 dpo : 51%
12 dpo : 62%
13 dpo : 68%
14 dpo : 74%
15 dpo : 80%
16 dpo : 88%
17 dpo : 92%
18 dpo : 99%
So technically you could be 14dpo and still have a chance that the test isn't catching the hcg in your system. It doesn't surge though like pp stated. Hope that helps!
First U/S 2/10 Possible TWINS! | Second U/S 2/24 TRIPLETS!!!