If I'm not mistaken, Inter are only two points behind last year's tally, so technically they are in line with last season's results. The most surprising thing is that the top of the table is more crowded than last year.
Inter have already lost their first head-to-head match against Juventus, and you're right, everything depends on how they react and approach the upcoming head-to-head matches.
Inter Milan have loss 2 of 5 games in Serie A and its not good result if want back to Scudetto race, not only loss from Juventus as the top team but also Inter defeated by mediocre team Udinese at games week 2.
For upcoming match, Inter Milan still have to face many top teams such as Roma, Milan and Napoli have consistent performance if can get three points great opportunity for in the domestic league race. In the early 5 games, Inter Milan have bigger chance back to top place because only 3 points gap with Milan already at the top standings awhile, its not too late for Inter improving their performance after losing 2 games.