我只是有点儿不舒服。this sentence speak just a little fell bad. 我一点也不舒服。this sentence speak very fell bad.

eat a little lunch. 吃点午饭。 there are a little beef. 有点牛肉。

"有点儿"and "一点儿" are both "a little ..." "有点儿"，usually be used to descrabe the feelings. for example:"我 有点儿 不高兴。" "一点儿"，often be used to dexcrabe the things. for example:"我有 一点儿 钱。"

一点儿 means some, maybe little.有点儿means HAVE some.

一点儿= a few, a little, some 有点儿= there is/are + 一点儿, have/has + 一点儿