What should i do?

So AF is officially a week late I have taken 4 tests and all negitive, I have a really hard time with pregnancy tests my first pregnancy I was reading negative in urine and blood work it wasn't until I had a cat Scan that I found out I was 4 1/2 months prego, second pregnancy I was able to find out through blood work at 12 weeks but I could never get a positive on a test with either pregnancy my hcg must run really low when pregnant idk should I make an obgyn appointment to find out or wait and see what happens?