Any ideas ?

So recently, I’ve had a pregnancy scare. My period was late and it usually never is. I waited a little over 2 weeks to take a test. All the test came back negative. I took a really cheap one at first and could’ve sworn I seen a line. I bought another test and then a digital test. I took the normal one first and it came back negative and then I took the digital which also came back negative. I still haven’t gotten my period, I’m 18 days late on cycle day 48. I was on birth control (the pill) for a little over a year and then switched to the patch. I got my period last month on time but I’m no longer on any form of birth control (besides using condoms) and still no period. All test say negative and I’m a little concerned because I still haven’t bled