Indian visa rules for such visas are evolving. Till recently, it was ok to reuse a multiple entry tourist visa and come right back. A few months back they put in a restriction of waiting out of India for 2 months before being allowed to re-enter --- due to some terrorist activities a year back which had an American citizen involved. Then they relaxed it for many categories, but not all. You never know how things will be in 6 months time since the security situation is being tightened again the last couple of days due to a bombing in Pune.
BTW, today is Feb 16 - how did you enter Feb 28???? If you are still in US, your best option at this time, without knowing future in advance, will be to get a 1 year visa if you can.
Also, if you are of Indian origin, you can get an entry visa valid for much longer duration. It might be cheaper to get a second visa than travel back and forth to Bangladesh and with no guarantee of return.
If you can describe your situation a bit more, I or others can throw out some more ideas.