At 19 weeks, I was just wearing bigger pants. I was mainly living in basketball shorts if I wasn't at work, and my pre-pregnancy work pants still fit at that point. I did have a pair of maternity capri pants that I wore, but they weren't getting stretched or anything. [I already had that tummy 'pooch' before I was pregnant, so I had some growing room.] But I didn't have to get a pair of the jeans with a full stretchy belly until about the end of August, which put me at about 5 months, I believe. :)
I was pretty big quickly( started showing at 8 weeks) so by the time I was 16-17 weeks I was fitting into my maternity clothes. Just remember you will get to the point where people know you are pregnant and to me the longer it takes the better because you don't want to get huge like me. Enjoy it while it last hun!
haha....I'm 33 weeks today and people are STILL coming up to me, asking if I'm pregnant (and it's pretty darn obvious, I think).
With a first pregnancy, you "usually" won't get as big so quickly.....Last time, I was so eager to wear my new maternity clothes and have everyone notice that I was pregnant, and didn't really have to until I was 17 weeks....and even then, I still wasn't big. I didn't really "pop" until I was 25 weeks.
This time, I had to get into maternity clothes much sooner. Now that I'm closer to the end and I'm not planning on having any more children, I'm pretty sick of my maternity stuff. I'll be happy to be able to shop for regular clothes again!!
I am still fitting into most of my regular pants. However, my regular shirts have become too short to wear because they are being pushed up by my growing belly. I am a taller person, so most of my shirts were never very long to begin with.
I think it just depends on your body. I started pretty small, only 117lbs and 5'5" so I fit into maternity clothes a lot sooner since I outgrew my clothes the minute I put on just a few pounds. I have also had to shop a few times throughout my pregnancy to find regular or maternity clothes that fit at different stages. I am now to the point of wearing my husband's t-shirts and sweat pants when I am not in public - and sometimes when I am - lol - because I am 40 weeks and ready to pop and nothing is comfortable! I have put on 30 pounds total. I wouldn't worry about what fits you and when because everyone is different based on original weight/size/etc. :-)
I am not sure what to tell you about the cramps - you may want to check with your doctor on that. Is it Braxton Hicks contractions maybe?
Im 21 weeks today & I still fit in all my regular clothes too! I have two pair of maternity pants which are both still too big. I wore on pair once just bc I wanted to try them out but I ended up pulling them up ALL day! People just started wondering if Im pregnant and they still think im so small for how far along I am. I dont fit in all my shirts though bc my boobs have doubled in size and bust out of everything. The only new things Im putting to use is bras haha! I'd rather stay as small as possible for as long as possible though bc thats less I have to buy just to only wear for a few months. When Im home I've surrendered to sweat pants & comfy shirts...mostly my bf's long sleeve t shirts :)