14 Days Late!

So I’m normally on birth control. The pill to be exact. Well I needed a refill this month, when I called my gynecologist they never called back and by the time I did get up with them it was a week after I was supposed to start, so I couldn’t start my birth control. I had unprotected sex once with my boyfriend he pulled out I know it’s not the best method but it happened. Now my period is 14 days late today. I’ve tried testing with blue and pink dyes the blue dyes keep giving evap lines and the pink dyes are negative. Should I go get a blood test done just to make sure? Or should I wait it out another month to see if it will come back then? I have no insurance (long story) but I really just need some advice. Sorry for the long post! TIA!