Suggest Treatment For Consumption Of Expired Ibuprofen Tablets

Hello, I have been taking 600mg Ibuprofen tablets, 2 at once, twice a day for 5days for tooth ache, 2 days ago I started to come out in a rash, small pimple like lumps (no visible white heads or blisters, just small red rash lumps). Today I found out the tablets are 3yrs out of date. Could they be the cause of the rash or could it be something else? I have changed absolutely nothing in the last week, this has been the only difference in the last week.