I sent the thank you letter following my interview within 2 days? it's been 3 weeks since the interview.?

indeed it would be pushy of you to try and write another letter. for that matter you shouldn't have written even the first one.

sorry to say that its not likely that you would be getting any call.

I would contact them and ask how the application process is going, letting them know you are interested in the job. I don't think you need to send a second thank you note (though that was a good move). Three weeks has been a good time to wait, and if you call up now, it will remind them of you. I don't think it could hurt.

Don't waste your time waiting for the interviewer to call you. Instead, you should look for other job opportunities. Based on my experience, waiting for 3 weeks or more could be a sign that they are not going to call you back. I'm not discouraging you. I'm telling you to move straight ahead and look for other opportunities.

You should send another thank you letter. You can send a gentle inquiry to check if a selection was made for the position. You can also call if appropriate. If you don't receive a response move forward to the next opportunity. Know that you will end up where you are meant to be.

I'd suggest that you call them. Start off by thanking them again for the opportunity to come in and be interviewed, then ask when you can come in again for the 2nd interview.

Don't send another Thank You note. But you could go ahead and call down there and ask to speak to the manager. Say you just wanted to follow up. They might tell you they found someone else or that they want you. Just depends. Good luck

Three weeks means that you very likely were not selected for the second round of interviews.

You are welcome to call or email to ask about the status of your application.

Another thank you would not make an sense.

You should call them if it's been that long