I think the appointment usually comes through the post, mine did anyway. Just ring them and check if it gets to 5 weeks and you haven't heard from them.
I haven't had mine yet so I'm not totally sure what they do and it might differ slightly in different areas, but I think they'll weigh you, check your urine and blood pressure, do a smear test if you haven't had one in the last 3 years, check that your uterus has gone back to the right position, check the stitched area if you had any, and discuss postnatal depression, contraception and any other issues you have
For Porscia I think they would check her heart and lungs, her hips and spine, her eyes etc.
That's what I'm expecting anyway, I might be wrong!