Lite spotting 3 days before AF due

So my husband and I are 34 been ttc for almost 2 hours and we did IUI without hormones for the first time last month. AF due 04/03 and I had pink spotting yesterday and small brown today and light cramping. I always start at 29-30 days which would be tomorrow or Saturday. We have a blood test tomorrow scheduled but I am racking my brain worrying. Trying to keep the faith and be positive but it's so hard. Has anyone ever experienced this and had a positive test? Please I need some encouragement!