Hey some advice please

My period is 28 days late and I have all pregnancy symptoms, I have thyroid disease so the home pregnancy test doesn't always show up because of my levels, was pregnant before had a miscarriage so I'm more nervous this time if I'm pregnant. And I've been spotting on and off for about three weeks. Does anyone else have simalar problems? I think I need to get a blood test does anyone know where you can get that done?