It is probably gas. Get some Gas-X strips and start walking around the house. I had surgery on 1/4 and was pretty uncomfortable the first few days because of gas. Once that went away, I was feeling awesome.
Keep in touch and let us know how you proceed.
Biotin is a B vitamin and the RDA is only 300 mcg. Hair loss is usually caused by a deficiency so I would expect anything over 300 mcg a day is sufficient.
I meant to say the vomiting while healing can cause a leak. Not likely, but it can. After it is healed, it cannot be "ripped open" by vomiting as far as I know.
My Surgeon said the stomach heals 50% within 72 hours and 100% within 3 months. Leakage is something that usually happens right away or later if you vomit a lot.