I and my gf had made out on 7th of February 2018 and it was mainly dry humping and she had even washed her hands before going to the loo but not very sure as I had got wet and spilled some on her hands. She has irregular periods (35-40 days on average) but has taken pregnancy tests on 26 Feb, 3,10,15,18,27 March 2018, all of which have been negative. But she still hasn’t got her periods. Also her last periods were on 20th January 2018, can we trust the pregnancy test.?