Talk to Gynecologist on Suspected Ectopic Pregnancy

i am previously having one suspected ectopic pregnancy five years back having one son with c section after that.Now I am pregnant and after some days of my late periods I started spotting and sometimes bleeding this continued for 9 days doctor said maybe it's the chemical pregnancy then she asked me to have beta HCG done I repeated test after 48 hours from 133 the value moves to 145.i am also having pain on and off in my left side of belly.i am so much worried please guide as the HCG level is very low so doctor said it's not possible to detect pregnancy through TVs.