Someone please tell me it's almost time to have my son!

Sierra • I have a 5 month old son, Gannan Michael. I`m 20 years young! My boyfriend and I are trying too get them close together in age so here I am TTC again! Baby dust too all!!
The past couple days I've been having period cramps throughout the day and night, head aches, back aches, and I feel like I have to have a bowel movement but when I try nothing happens. 
Is this the first signs of early labor?? 
I plan on telling my doctor this Friday when I go, but everytime I tell her a symptom she comes back with "It's normal" and that's it. 
She won't check me for dilation until I'm 39 weeks, I'm currently 38 week and 2 days.