If M Slowbro EX attacked with "Loll Roll Spin" last turn, then next turn attacks when it is Confused and flips tails, does it do 130 damage to itself?
No, a failed Confusion flip does not do damage, it places 3 Damage Counters. The 100 bonus damage is not applied to damage counters being placed.
Source: Evolutions FAQ (2016-11-03), TPCi Rules Team (2016-11-03)

Relevant cards

Note: All applicable cards may not be listed below.
XY12_27