Is it possible to miscarriage and not know it

So in July I was spotting which was pretty normal for me I have a brain tumor and it’s effecting my ovaries .. so I took it as I had a period .. the following week after this was said and done I got my wedding dress and my mom and my bridal shower kept asking me if I was pregnant and I said no I had af last week ... the following week after that i was spotting , then I had a PAINFUL blood clot ..

it’s taking me awhile to come to conclusion cause we been trying for 2 years now and I just can’t imagine if we lost one without knowing I was pregnant what kind of mom will I Be if I didn’t know I was pregnant in the first place