Breast pump for a first time mum

I use Avent at home and Real Bubee in the office. Avent is good enough and less expensive than most of the established pumps. Real Bubee is extremely cheap at less than $30 for double pump; however, I find that it is painful. Hence, I would only pump max 10 mins for each breast. When I accidentally pumped a little longer than 10 mins, I bled...had to throw the milk. 💔