Yes, head and falsetto are the same. Holding the same note from chest to head voice will strengthen your falsetto in the lower registers(of your falsetto) and by the same token strengthen your chest voice in the upper registers of your(chest voice) range. Once you can hold a note in this manner then try to keep your falsetto at the same volume as your chest voice. This will force you to concentrate on the amount of 'air' you need to force out to maintain pitch/volume when changing 'voices'. Practice good technique then forget about it when 'in the moment' and eventually the tendency to sing incorrectly will feel uncomfortable and you'll be able to 'yodel all night' without your voice becoming ragged. There's dietary considerations, too which will lower your 'phlem count'. Steamed veggies, poultry(no skin), fish and a reduction in diary consumption will contribute to a 'cleaner' falsetto. Taking a 'yogic breathing' course will help in diaphram control and it's my belief smoking is a yodeling inhibitor. Have sung professionally for over 20 years and can still hit a Bb over middle C fairly easily in my chest voice and my falsetto is still very pure(F over high C). Lower range is to a D-2 octaves below middle C. The diet thing will take some time for your body to adjust, but you 'will' be able to tell the difference, especially diary products. Glad to have been able to help. Try to supplement these suggestions with a good vocal coach. They may be able to interpret my somewhat confusing prose syle.