Your dog's digestion rate isn't affected by his size as much as by other factors, including the type of food you give him, the amount of exercise he gets, the amount of water he drinks and more. For example, an average dog -- big or small -- takes between four and six hours to digest canned wet food.
Every woman's metabolism is different, but as a general rule of thumb, you should allow 1 day for every 1,000 units of hCG you injected. The standard hCG dose is 10,000 units; thus, 10 days after the shot, the synthetic hCG should be gone and you should be able to test for pregnancy without detecting the shot. However, you should ask your doctor what the recommended protocol for your dosage is..
After a week of delay, hCG levels will be high enough to be detected. Wait for 21 days to take a pregnancy test after intercourse to be 100% sure of the result if you have a regular menstrual cycle. If you choose to do the pregnancy test the first day after a missed period and it is negative, then wait a little longer.