I need advice!!

Irania
I totally skipped my period in February and I still haven't gotten it and I am now 18 days late I got tested twice at the doctors and I tested once at home and all negative I'm so confused i haven't been stressing on it my hubby and I are certain I am pregnant can I be wrong should I get blood work for the test? We want to be positive but we don't want to be let down!! 😣😩😭🤔
*UPDATE* I'm 21 and my period has always been normal I've always been on time but this February was the first time I actually missed it! 
ANY ADVICE!?!