8 weeks pregnant and 7 weeks PO Tummy tuck - what complications can this cause?

If you had your tummy tuck after you were already pregnant, your pregnancy test should have been positive on the morning of surgery and resulted in a cancellation of the procedure. It is possible to have a pregnancy that is very early and not detected by urine testing. The OB/GYN needs to be involved in your postoperative care.

Nowadays modern anesthesia drugs are compatible with pregnancy and are, in general, non teratogenic (harmful for embryo's development). Best you can do is have a talk with the anesthetist in charge, review the therapies applied and discuss one by one their effect, you'll receive the right advice. Most likely you did not receive any toxic drug; keep in mind pregnant women receive regularly operations: apendix, fractures, severed tendons, cesarean section, etc., so aneshtesia is compatible with pregnancy in wide margins.However, you and your baby run a real risk because the growth of the now embryo and later baby will be impaired or harmed by the muscular work
done suring the TT (check this point, some surgeons do not perform muscular work, if the surgeon did not plicate the muscles then you are safe). Even your own health is in rigk for venous thrombosis or pulmonary collapse and other issues.I recommend 2
options in case you had muscular reinforcement done during TT:-undergo immediately surgery to release the muscular
plication your surgeon did to reinforce your abdominal muscles at the
rectus and/or oblique units, so that to release any tighness agains your phaetus growth; this brings backs the bloating and looseness of your muscles-interrupt your pregnancy (based on your ethics and legal local regulations)This imcompatibility does not happen if the TT had be done more or less 1 year prior to getting pregnand; this is so because the muscular reinforcement scars become elastic with time, unlike when they have been recently done, at early stages they act as real barriers for any abdominal increase, thus affecting your uterine development.You must address this issue urgently with all the stakeholders: surgeon, anesthetist, gynaecologist, husband, lawyer, etc.

Most surgery centers require a pregnancy test the day of surgery to prevent this. My advice is to seek genetic consultation from a geneticist and also ask your OB doctor. 

This situation has happened many times due to the time required to make the hormones picked up in our standard urine pregnancy tests. I have had 3 patients to tell me they were probably pregnant during their surgeries. Fortunately there have never been any consequences as the births were normal. It will be important to discuss this with your obstetrician to review the anesthesia and postop medications and follow the baby with tests and sonos in development. At 40 you will have special considerations also. After tummy tucks pregnancies usually go routine in that the abdomen will stretch to accommodate the baby. I would like to congratulate you on your first pregnancy and wish you the best luck. 

I've never heard of anyone getting pregnant within a week of and abdominoplasty. I don't see a problem bringing the pregnancy to completion but my guess is you'll suffer more than the average patient.