Typically, blood that is only visible by microscope means the problem is in the upper urinary tract (kidneys), while visible blood means the problem is in the lower tract (ureters the tubes from kidneys to bladder, the bladder, or the urethra which is the tube from the bladder to outside). But, of course, this is not always the case.
In almost all cases, blood in the urine is nothing serious. But since your mom has kidney problems, then you need to have it thoroughly checked out. I can't remember the cause of her kidney failure? It is possible that you have the same condition.
Blood in the urine is usually caused by an infection - but it can be caused by many many many other things, the worst of course, is cancer all the way down to trauma (e.g., intercourse). Some people have an infection and do not know it. Others have inflammation which precedes infection and that will cause blood in the urine too.
Bottom line is that it showed up again, so you need to see the pee doc
again.