My Oxygen Level Is Running In The Eighties During The

My oxygen level is running in the eighties during the day. I had a sleep. Study and they told me to use the oxygen at bedtime. I test myself during the day because I get light headed and it's low. The lowest was 78, but it's average is 86. I'm going to Reno to see my daughter next month, is this going to be a problem? Will I need
To have oxygen all the time. I stay at home most of the time taking care of my mother for twenty five years, I quit smoking three years ago. I don't have sleep apnea, but I am over weight. I've had four back operations and two of them were last March then again in September. My back still hurts so my excersize is doing everything in the house. Can you give me some advice?