is trannsfer of endometrium out side the uterus
. Endometriosis is known to cause difficulty in conception/ painful,excessive bleeding in menses.
The uterine contraction & pain in 2 months pregnancy
is mostly due to progesteron deffesiensy.Progesteron supplement controls such pain.Consult a gynecologist in this respect.
Another cause I think in your case is phobia
you have developed for endometriosis/you being more concerned for safety of pregnancy.
In such a case Positive thinking/a good session of counseling with Gynecologist/psychotherapist would suffice.