Shelly,
I defineately recommend an office chair that is adjustable. I have gotten them at yard sales, second hand stores and finally Staples. They often have sales of less than $100. It is the best money you will ever spend. To sew, serge and embroider I have my chair in the middle between two tables. The serger and embroidery machine are on one wall. The sewing machine is on a table that is in free standing so I have room to drape quilt projects. I swivel my chair back and forth between the machines. I have a chronic autoimmune disease that makes me have major muscle problems. The chair allows me to sew longer as I can sit at the height etc. best to relieve any kind of arm, neck and back strain. My sewing tables are fold up ones from Staples also. My husband who is a machinest cut the legs down to make them just the right height for me. The chair I use at my computer is one of the ones I got second hand for about $20. It would have probably cost several hundred dollars new.
Good luck