Advice please?

So my period is due in 5 days and my partner and I have been ttc but only started this month, but last month I promised a friend i would go to her bday party and drink, but I wanna be safe that I’m not pregnant, and not sure if testing tomorrow would do anything or be way to early? But I can’t tell her I have been ttc and can no longer drink with her because she just lost a baby and her ex best friend just got pregnant with her ex partner (they were cheating together and she found out just after she lost the baby) so I don’t know how to say I’m trying for a baby without her getting upset also as i already have a daughter who will be 1 on the 12/07, and advice would be nice please, thank you. 😁

Sorry if it sounds confusing