My suggestion would be to find out what your room is doing before seeking solutions to issues you may or may not have. If you live near a local B&M store that installs home theatres, or an AV installer, chances are they have a program that will analyze your room. They should do this for a reasonable price - you are basically asking them for a quote to treat your room with whatever is needed and they will make suggestions about what sonic measures should be taken.
Whether you accept their bid to do the job or not, you have to be prepared to pay a reasonable fee for their time and expertise to analyze your issues.
If you still want to do it yourself, come back here and ask specific questions about what you need to do to rectify specific issues.
Whether you accept their bid to do the job or not, you have to be prepared to pay a reasonable fee for their time and expertise to analyze your issues.
If you still want to do it yourself, come back here and ask specific questions about what you need to do to rectify specific issues.