Electric problem

[slick78]

Ok so I got my lights working on my 1978 stepside. I changed my dimmer switch like I was adviced and I also put new head lights and everything was ok. But, I still got a problem. When I put the high beams on the right side don't work so I kept trying later that day and my right side worked but not my left this time and now their also both dimmed when before they worked fine. What's going on? I'm lost. Could it be the plug where the dimmer switch plugs too?. Maybe light switch or my battery? Please help!!