In need of advice :(

How do you mentally prepare yourself to take a test? I'm taking one in the morning as soon as I wake up and even though my partner is trying to reassure me that no matter the outcome everything will be fine, I still feel so much dread.. I'll be 15 days late tomorrow and I have none of my usual period symptoms whatsoever and quite a few minor pregnancy symptoms but I've been putting it off for so long I'm now just quite anxious. I haven't been stressed out up until now and I really just need any advice how to get past this stage. Thank you ladies xx