Worried

Hi everyone so I've been a lil worried kinda feel like I need to talk and get stuff out my chest . I'm a mother of two and one on the way . I'm due August 14,2016 this Sunday . I'm freaking out both my pass pregnancy where easy and none stressful . They both came naturally my first was to weeks early from her due date and my second one week early . Anyways I'm scared and a lil freaked out because this is the longest I've ever been pregnant .my old obgyn never let me go this far along in my pregnancy because I'm a small person . This time around I'm huge never have I been this big before .  I feel very upset with myself I feel like my body is not doing its job . I'm 1 cm dilated and my cervix is still a bit thick . What should I do should I let things come naturally and stop overthinking the worse or what ?