How do you no if you a good mum or not??

Im 19 and gave birth to my first child 3 weeks ago, i feel im a good mum as im a single mum it is hard but i am giving all i have to becoming the best mum i can be for her i have the love and support of my family and they are always there when i need them but some times i feel if i ask for help it makes me a bad mum that cant cope so my question is how do you no if your a good mum x