period is late. not just "hey maybe my period is coming late" like, "yo I'm ur period and I have moved away and you're never seeing me or signs of me again" late. negative test. dr very dismissive. where do I go from here ?

So my period is late. I normally have a 33-35 day cycle and I am now on day 42. I've never missed a period before. A few months ago I had a light, short period but SOMETHING still came. I have taken a test first thing every morning and nothing. Zilch. Zero! I buy first response, but instead of weeing on the stick I do so in a test cup and dip the test in. (It's not a dip test, but I find this easier to do, can this impact results?) My dr was pretty dismissive and basically said that because my husband and I are younger (27 & 23) we shouldn't be in a rush to conceive like some of her older patients that are 33+ and said I may have miscalculated my dates. I haven't. I know I am late, and I'm not in a rush but still want to know what's going on with my body??? I have been very nauseous, but haven't actually thrown up I have just dry heaved about once or twice a day. The nausea comes and goes. Does anyone have any advice as to where to go from here ?