Has anyone had negative urine tests but actually been pregnant?

[AnxiousMum2015]

So here's the deal,
My last period was back in late December 2020. My partner and I have always used the withdrawal method (no hate please ) mainly down to myself having awful reactions to hormonal contraceptives along with the copper coil. Anyways we had a slip up around week 2 of Jan where he pulled out but still hit the target if you know what I mean.. sorry if TMI. Now my period didn't come end of Jan or end of Feb. All urine tests are coming back negative.

Its extremely unlike me to miss 2 periods.
I was wondering if anyone has had anything like this and actually ended up being pregnant in spite of the urine tests saying otherwise?.

I would like to add that I have a son already, when I was pregnant with him I showed on a test the day after my missed period. I have been in contact with my GP who just keeps telling me to take a test again. I have gone through about 20 of those urine dip test strips.

Any help or advice would be so greatly appreciated please,
I feel like I am loosing my mind.

Yes I have had this. I had a pregnancy confirmed by bloods and scan as nothing showing at all on urine tests. Doctors were a bit baffled and said it made no sense but sure enough I was pregnant. Unfortunately I lost that pregnancy around 6 weeks but even to that day my hcg levels wouldn't show on urine tests.

I'm currently 6 days late with pregnancy symptoms and negative tests so I'm going a bit loopy and think I'll book on for bloods if nothing by next week. So yes it is possible but no idea how!