Sorry to be the bearer of bad news, but I wouldn't think so. Most REs want to see a lining of at least 7mm (8 and above preferable). Was this measurement taken at or after ovulation? Hopefully it was an early measurement and will continue to grow! Good luck to you!
it is, and you should be seeing a doctor and having that monitored. If your uterine lining is too thin, it may be difficult to maintain the pregnancy. There are drugs available as well as hormonal treatment to help build up the lining. You should very definitely inquire about it with your doctor, then follow his/her advice.
Yes, it is possible. Some women have experienced a "first" period then learns a couple of weeks later that they really are pregnant. It is possible that it could be implantation bleeding caused by the fertilized egg to attach itself to the uterine wall.
Ask your doctor
Oxytocin
That is a very broad timetable. Some girls get pregnant right away, though others can't get pregnant for years. Also, because the uterine lining gets broken down, it may be harder to maintain a pregnancy. My husband and I got pregnant after being off the depo. I only took 1 shot and was off for four months before getting pregnant and at 6 weeks I had a miscarriage. This was my second miscarriage and i believe the baby was somehow detached from the uterine lining, possibly because it was too weak to support the growing fetus.
This could just be your uterine lining coming away which is normal, it just came away after your period instead of with it.
Yes.
there is a chance you can be pregnant
No.
I am not sure how early you mean right away, but about five weeks is the earliest they can tell through an ultrasound. But at only five weeks a heartbeat will not be detected yet, just an embryo and the thickening of the uterine lining.
Yes he can
Possible if you took no protection and were ovulating.
Oh yes! It is very possible. I was on it for awhile and then stopped for about a month and in between that period I got pregnant. So Yes it is very possible. Go to the doctor sweetheart.