Have I "popped" yet?

So, I've been reading all of the pregnancy books and filling out my "baby belly book."  I've read about how women may want to start buying maternity clothes or borrow their husband's sweatpants at around week 13.  My baby belly book has already asked me when I "popped".  I don't know what to write.  I have 3 stretchy jeans that I can still fit into, but these are now becoming too tight.  I have to button them up way down below my belly button, sort of like how those guys with big guts wear their pants. 

There's nothing wrong with bellies like this in general (I guess), but at only 13.5 weeks, I don't feel like I should be at that point.  I do have genetics on my side, though.  My dad has the biggest, hardest pregnant-man belly I've ever seen.  I bet he wears a size 34 pant but would really need a 46 if he wore the pants up in the normal manner.  And, as all of the people who know me and have seen me eat can attest, my belly gets really distended when I overeat, so it looks like I'm about 5 months pregnant.

I'm 5'3", barely.  At my best weight (February of last year) I was at 119 lbs.  At my worst (during my senior year of college), I was 130 lbs.  When I stepped on the scale this morning, I was 129 lbs.  129.  And here's my dilemma.  Not that I want to diet while I'm pregnant...hell, when my midwife told me to gain 10 lbs by 20 weeks I was ecstatic...it's just that I don't know if I'm technically "showing" or if it's just the extra 10 lbs I've put on in a year.  It's depressing especially when i put on the cute maternity clothes and I don't know if it's because I'm really showing or if it looks like I'm showing because I'm +10 lbs and bloated. 

Waaa...Waaa...Waaa.  I need to get over it, right Bill?