Should I take another Covid test?

My cousin tested positive for Covid two nights ago (11/24) me and my 3 year old son had very close contact with her and her children on 11/20 (my son was with his father and I was unaware they all were showing symptoms on this date), 11/21, and 11/23. My son developed sinus infection symptoms on 11/22 and I developed them 11/23. I took an at home test yesterday after she told me her, her children and husband all tested positive and mine came out negative. My son is already almost better just residual drainage and my symptoms are going away pretty quick too. If it was Covid shouldn’t it come back positive since I’m already showing symptoms and we were exposed about 5-6 days ago?