I have 35 days to go I feel so nervous

I'm a reck every time I check how many days I have left j feel a nervous wreck this is my 4th baby I'm terrified about the after pains especially my 3erd was bad enough don't no why I'm so nervous and it don't help that I'm measuring 2 weeks behind I keep thinking there is something wrong with her I have mental health issue bipolar disorder but has never affected my parenting as such I have a good support network my partner is full on dad wil get up for feeds change bums and anything really he's really good but I'm so nervous everytime I think of giving birth or how I'm going to look after her after a 6 year age gap from my last baby I actually want to puke I actually feel sick my tummy turns and my heart pounds xxxx