The signs of labour at 33 weeks

hello people im 21 years of age and pregnant with my first beautiful baby boy but i need advice, i dont know if im in slow labour or what but i go to the toilet and have a wee then stop then another wee would come and this would happen 4 times then i notice diarrheoa then it all stops im having back aches and cramping in my leg what do you think is going on any advice please thank you xx