Shipping Priority Mail from USA to Singapore?

So I read online on the USPS website that Priority Mail should only take 8-10 days to get from the USA to Singapore. I recently sent a package through Priority there, and it's been almost the full 10 days, but it has yet to show up. :/

Is it possible for it to be delayed and still show up safe and sound, or am I going to have to end up refunding the buyer in a few days? .__.

...Also if someone would please explain to me why on the USPS website it says that a Priority Mail Flat Rate box is automatically insured up to $100 if then I go to figure out how to file a lost/damaged claim it says you can't unless it was sent Registered. -__-;; I didn't even know Registered existed until a week ago when a friend in England told me about it, because the USPS people always told me the only way to insure/track anything going out of the country was to use EMS.

Gotta love our postal service. */sarcasm*

Thank you in advance!

 

Aceinit, I double checked online and found that it's indemnity coverage that's now provided free of charge to the small Priority Flat rate boxes if it's going international, which is why I thought it came with insurance. Which basically it does, but it's just a fancy way of saying it...? I can't check with my local post office right away as I'm out of state visiting family, but I've already planned a looong talk with them over why they never explained all of my shipping options to me and make them do so then. -__-;;

...This is the same post office that just recently tried to deliver a package while no one was home, and my roommate signed the orange slip to OK the package being left if they re-delivered and again no one was home, and they completely ignored it. Also we've had mail that's never gotten to the mail box because the carrier was too lazy to walk the three steps up to the door and instead shoved the letters and magazines in the metal grating surrounding the porch for me to find hanging out for the world to see when I got home. So frustrating!

But thank you, it's good to know that there's a little wiggle room in shipping wait times before we both started panicking. xD

 

Thank you so much for leading me to the customs number Lucyhayashi!! I found it on the form and threw it in to USPS tracking, and found it had taken a week to move from my post office to a 'foreign center' in another state, and is listed as in transit to destination. I hope it got out of the US before the 4th of July otherwise it proabably was further delayed. I'll let my buyer know anyway and give her the number.

And I had no idea registered was such a hassle. o__o;; My friend in England said from the US to her wouldn't be too bad price wise, but it does sound like a ridiculously expensive and time consuming option for other countries. Part of it might just be where its going; When I mailed the package out, I had my standard customs form all filled out and ready and they made me fill out a bigger, different one instead. *faceplam* I've never had to do that before so that should have tipped me off right there. :b

Honestly, I'm just going to stick with EMS after this unless a buyer tells me otherwise. >< USPS is so confusing and I've been going in circles on the website trying to find the info I want...