Yes, you can limit the campaign budget. Under budget option you can set: ASAP or EVEN.

ASAP pacing means you will get the traffic due to your daily budget as soon as possible, while EVEN pacing means the traffic will be spread evenly during 24 hours/hours chosen in the timetable.

Generally ASAP budget pacing is highly recommended in the following situations:

1. If your campaigns do not meet daily budget goals.
2. There are whitelists/source sampling/any other features within campaign settings which reduce the amount of traffic significantly.

The minimum budget is $5.