Hug level are they ok

Patient: So i had sex only once in dec. i had sex on dec 21st. i was suppose to get my period on the 26th of dec. i has some light spotting that was pink then it went away. took a pregnancy test neg. then i retook a pregnancy test n the 2nd of jan. it came back positive. went to drs and it was positive also. they ended up doing a blood test that day. my hcg level was at 28.2. so they said they wanted to retest on the 5th of jan in the morning to see if they double. my question is is 28.2 for hug good for only being 12 days after intercouse and conceiving. is that normal? how far along would i be? and why is it the the test showed up that early. and when the earliest you can test positive with home test. thank you

Symptoms: Hcg levels

Doctor: Hello,The best and the most sensitive way to test and check for pregnancy is the serum beta hcg level test and it can detect pregnancy after 7 days of intercourse if the lady is in her fertile period. The high levels which is more than 1 indicate that there is pregnancy as hcg is only secreted by embryonal syncytiotrophoblastic cells and hence highly specific. On the other hand home pregnancy test are sensitive when the hcg levels have already crossed 5000, so serum beta hcg test is superior.A value of 28 hcg, is good enough value for 12 days and confirms your pregnancy. A repeat test after 48 hrs is to look for doubling of levels which indicate towards an ongoing viable pregnancy which is growing by producing more and more cells and thereby hcg.I hope i have answered your query in detail,wishing you good health,regards