4 weeks and bleeding

Since 10 jan. When i found myself preg. Till now 14 jan. I had slight very very super slight cramp feeling. All seems fine. 10 jan i went clinic to cfm on pregnancy. doc mention im abt 4weeks preg as my 1st day of last mense is 13th dec. N im regular. Everyday was ok. Slight nausea. Sleepy. 14 jan. I went nap 2 hrs. Woke up with a feeling of full bladder. And i went pee. Wipe. Blood on tissue. Look down. Toilet bowl is just red colour. Went kkh o&g. Did a transvaginal scan. Cant see baby in womb. Did blood test. My hcg is near 900. Monday need do blood test again. Anyone had same experience? Do advise.