First response pregnancy test

Is there anything to the whole pregnancy test line being darker and meaning multiples? I tested out of curiosity and not planning to be expecting one one of the first respond (non digital tests) two days after missed period. And the test line is actually darker than the control line.... at only 4 weeks. Is there anything to this? Also is it ok to be mild to moderately cramping still? I’ve been cramping since two days before missed period.... about 5 days total now