Worried. Spent $150 that I REALLY don't have to send a package and the post woman never gave me a receipt...didn't notice until way after too. I asked the person I sent it to to let me know when it arrives. The guarantee was 4-7 days (though generally 4)...it's been...well, 8. so maybe it's OK. Without the receipt I can't get any money back, and bleh. I can't even contact the gift recipient as she's mad at me and wants highly limited contact. But she said she'd tell me.
Mind you, I paid for it to arrive in 4-7 business days, I did not pay for it to arrive any later than that and I'm entitled to a refund (says so on post website). Why didn't I notice the receipt missing? Ugh. I just woke up, damnit, and already I'm stressed out.