Back pain after 3 days of ovulation has little to do with pregnancy. The chances of pregnancy during intercourse during ovulation are higher, but back pain is not a typical manifestation of a fertilized egg after formation. It takes 7-10 days for a normal fertilized egg to come to term and most of them do not show any discomfort during this period. If you have back pain 3 days after ovulation, you may consider the increase of hormone secretion in your body during ovulation, which causes lumbosacral pain and swelling. If the symptoms cannot be relieved, consider other factors, such as pelvic inflammation, lumbar spine or lumbar muscle fatigue, and suggest going to the hospital for examination to clarify the cause for treatment. After waiting at least 10-14 days after having intercourse during ovulation, you can go to the hospital for a direct blood HCG test to clarify pregnancy, it is not possible to have symptoms in only 3 days. If you want to determine pregnancy by early pregnancy test, the earliest you can determine it is 15 days after intercourse. If you want to exclude ectopic pregnancy, you can perform an ultrasound to determine the location of the gestational sac. If pregnancy is clearly established, pregnant women should take proper rest, avoid straining, do not do heavy physical work, avoid incorrect posture and movements, do not stand or sit for a long time, and keep their mood relaxed.