I have been diagnosed with adult adhd in 2015. ive been on and off medication mainly due to the way its made me feel. i would like to start again - concerta worked the best but the dosage was too low at the time. any advice on getting started?

Start simple: These meds usually provide any beneficial effect they can within the first few days of use. Starting with the lower dose form (18 mg) with a gradual increase in weekly increments (+18 mg) should help you reach a level you find useful. Once you find the level you feel works without making you feel odd you can let your prescriber know this works best.