Kilmarnock skipper Gary Dicker says the after-effects of Covid-19 left him with "a constant headache for a week".
Dicker began to feel unwell a couple of days after helping his side to a 1-0 win at St Mirren on 26 September.
The Irishman, 34, was then one of six positive cases at Rugby Park that week, leading to the squad going into self-isolation and the game against Motherwell being postponed.
"I had it probably the worst of all the lads," said Dicker.
"[Initially] I just felt a bit achey, like a had a cold. I lost my sense of taste and smell later that week.
"I got better, but then started getting headaches. The after-effects - I had a constant headache for about a week. That went and then I was alright."
Kilmarnock face a disciplinary hearing next week after being charged with breaching Covid-19 protocols in the build-up to the postponed Scottish Premiership game with Motherwell.
After the club forfeited a League Cup tie against Falkirk, Dicker made his comeback on 13 October in a depleted side beaten 3-0 by second-tier Dunfermline Athletic.
The midfielder says it took him "three weeks to feel completely right" after first experiencing symptoms.
"It's more of a long Covid they talk about now and I think that's probably what I had," he added.
"If people who get it have underlying issues, you can see why it will affect them. I'm young and healthy and it knocked me."