TTC have lost three so far

Ive lost three babies two of them due to BC not knowing that I was pregnant. This recent one was lost unexpectedly. I was taking prenatal vitamins thinking it would help due to that I do smoke black&milds on a regular. I need help on what should I do. I took a test early Saturday morning which the test had a default to it. I was planning to test again next Friday but had rough sex last night and this afternoon I began to spot bright red blood with very sharp cramps in the lower part of my abdomen. What would be recommended to change this. I'm really not sure when my ovulation is due to BC have me with a period every 30 days. What should I do because we both want a child today I'm just loosing hope at this point😭😭 I'm really sad because I was 4 days late and now I'm spotting bright red blood. I need help and encouragement pleasseee!!!