Unwanted pregnancy. Chance of pregnancy?

Sir/mam me and my gf have sex in 18 January 2018 with a condom..but first time I wear the condom opposite side..after that I will turn that and wear properly..I think some precum stay in front side of the condom but I remember I will clean the precum with my hand..can there any chance of pregnancy? After that we will sex again in 29 January but this time it was a anal sex..after that she will take a unwanted 72..after 7 days she have a bleeding after taking unwanted 72 and it stays for 6 days..after that she have some lower abdomen pain and lower back pain.. she have vomiting for just 2 time in one day..after that we are done serum beta HCG blood test after 29 day of the anal sex..and result comes 0.48mIU/mL what is that negative or positive? What is The result means negative or positive?And after that can there any chance of pregnancy? Pls answer me in details...I am very tensed..pls tell me...can there any chance of pregnancy?